clock speed changed, pending correponding SPI changes

The Beta Parameter is not dimensionless, and has unit kelvin.
Incorporate that into the type system.

.gitignore

@@ -1,2 +1,5 @@
 target/
 result
+*.bin
+
+__pycache__/

README.md

@@ -23,7 +23,7 @@ cargo build --release
 
 The resulting ELF file will be located under `target/thumbv7em-none-eabihf/release/thermostat`.
 
-Alternatively, you can install the Rust toolchain without Nix using rustup; see the Rust manifest file pulled in `flake.nix` to determine which Rust version to use.
+Alternatively, you can install the Rust toolchain without Nix using rustup; see the `rust` variable in `flake.nix` to determine which Rust version to use.
 
 ## Debugging
 
@@ -84,9 +84,7 @@ invalidate the first line of input.
 
 ### Reading ADC input
 
-Set report mode to `on` for a continuous stream of input data.
-
-The scope of this setting is per TCP session.
+ADC input data is provided in reports. Query for the latest report with the command `report`. See the *Reports* section below.
 
 
 ### TCP commands
@@ -94,42 +92,41 @@ The scope of this setting is per TCP session.
 Send commands as simple text string terminated by `\n`. Responses are
 formatted as line-delimited JSON.
 
-| Syntax                           | Function                                                                      |
-|----------------------------------|-------------------------------------------------------------------------------|
-| `report`                         | Show current input                                                            |
-| `report mode`                    | Show current report mode                                                      |
-| `report mode <off/on>`           | Set report mode                                                               |
-| `pwm`                            | Show current PWM settings                                                     |
-| `pwm <0/1> max_i_pos <amp>`      | Set maximum positive output current                                           |
-| `pwm <0/1> max_i_neg <amp>`      | Set maximum negative output current                                           |
-| `pwm <0/1> max_v <volt>`         | Set maximum output voltage                                                    |
-| `pwm <0/1> i_set <amp>`          | Disengage PID, set fixed output current                                       |
-| `pwm <0/1> pid`                  | Let output current to be controlled by the PID                                |
-| `center <0/1> <volt>`            | Set the MAX1968 0A-centerpoint to the specified fixed voltage                 |
-| `center <0/1> vref`              | Set the MAX1968 0A-centerpoint to measure from VREF                           |
-| `pid`                            | Show PID configuration                                                        |
-| `pid <0/1> target <deg_celsius>` | Set the PID controller target temperature                                     |
-| `pid <0/1> kp <value>`           | Set proportional gain                                                         |
-| `pid <0/1> ki <value>`           | Set integral gain                                                             |
-| `pid <0/1> kd <value>`           | Set differential gain                                                         |
-| `pid <0/1> output_min <amp>`     | Set mininum output                                                            |
-| `pid <0/1> output_max <amp>`     | Set maximum output                                                            |
-| `s-h`                            | Show Steinhart-Hart equation parameters                                       |
-| `s-h <0/1> <t0/b/r0> <value>`    | Set Steinhart-Hart parameter for a channel                                    |
-| `postfilter`                     | Show postfilter settings                                                      |
-| `postfilter <0/1> off`           | Disable postfilter                                                            |
-| `postfilter <0/1> rate <rate>`   | Set postfilter output data rate                                               |
-| `load [0/1]`                     | Restore configuration for channel all/0/1 from flash                          |
-| `save [0/1]`                     | Save configuration for channel all/0/1 to flash                               |
-| `reset`                          | Reset the device                                                              |
-| `dfu`                            | Reset device and enters USB device firmware update (DFU) mode                 |
-| `ipv4 <X.X.X.X/L> [Y.Y.Y.Y]`     | Configure IPv4 address, netmask length, and optional default gateway          |
-| `fan`                            | Show current fan settings and sensors' measurements                           |
-| `fan <value>`                    | Set fan power with values from 1 to 100                                       |
-| `fan auto`                       | Enable automatic fan speed control                                            |
-| `fcurve <a> <b> <c>`             | Set fan controller curve coefficients (see *Fan control* section)             |
-| `fcurve default`                 | Set fan controller curve coefficients to defaults (see *Fan control* section) |
-| `hwrev`                          | Show hardware revision, and settings related to it                            |
+| Syntax                                    | Function                                                                      |
+|-------------------------------------------|-------------------------------------------------------------------------------|
+| `report`                                  | Show latest report of channel parameters (see *Reports* section)              |
+| `output`                                  | Show current output settings                                                  |
+| `output <0/1> max_i_pos <amp>`            | Set maximum positive output current, clamped to [0, 2]                        |
+| `output <0/1> max_i_neg <amp>`            | Set maximum negative output current, clamped to [0, 2]                        |
+| `output <0/1> max_v <volt>`               | Set maximum output voltage, clamped to [0, 4]                                 |
+| `output <0/1> i_set <amp>`                | Disengage PID, set fixed output current, clamped to [-2, 2]                   |
+| `output <0/1> polarity <normal/reversed>` | Set output current polarity, with 'normal' being the front panel polarity     |
+| `output <0/1> pid`                        | Let output current to be controlled by the PID                                |
+| `center <0/1> <volt>`                     | Set the MAX1968 0A-centerpoint to the specified fixed voltage                 |
+| `center <0/1> vref`                       | Set the MAX1968 0A-centerpoint to measure from VREF                           |
+| `pid`                                     | Show PID configuration                                                        |
+| `pid <0/1> target <deg_celsius>`          | Set the PID controller target temperature                                     |
+| `pid <0/1> kp <value>`                    | Set proportional gain                                                         |
+| `pid <0/1> ki <value>`                    | Set integral gain                                                             |
+| `pid <0/1> kd <value>`                    | Set differential gain                                                         |
+| `pid <0/1> output_min <amp>`              | Set mininum output                                                            |
+| `pid <0/1> output_max <amp>`              | Set maximum output                                                            |
+| `s-h`                                     | Show Steinhart-Hart equation parameters                                       |
+| `s-h <0/1> <t0/b/r0> <value>`             | Set Steinhart-Hart parameter for a channel                                    |
+| `postfilter`                              | Show postfilter settings                                                      |
+| `postfilter <0/1> off`                    | Disable postfilter                                                            |
+| `postfilter <0/1> rate <rate>`            | Set postfilter output data rate                                               |
+| `load [0/1]`                              | Restore configuration for channel all/0/1 from flash                          |
+| `save [0/1]`                              | Save configuration for channel all/0/1 to flash                               |
+| `reset`                                   | Reset the device                                                              |
+| `dfu`                                     | Reset device and enters USB device firmware update (DFU) mode                 |
+| `ipv4 <X.X.X.X/L> [Y.Y.Y.Y]`              | Configure IPv4 address, netmask length, and optional default gateway          |
+| `fan`                                     | Show current fan settings and sensors' measurements                           |
+| `fan <value>`                             | Set fan power with values from 1 to 100                                       |
+| `fan auto`                                | Enable automatic fan speed control                                            |
+| `fcurve <a> <b> <c>`                      | Set fan controller curve coefficients (see *Fan control* section)             |
+| `fcurve default`                          | Set fan controller curve coefficients to defaults (see *Fan control* section) |
+| `hwrev`                                   | Show hardware revision, and settings related to it                            |
 
 
 ## USB
@@ -186,14 +183,16 @@ postfilter rate can be tuned with the `postfilter` command.
 
 When using a TEC module with the Thermostat, the Thermostat expects the thermal load (where the thermistor is located) to cool down with a positive software current set point, and heat up with a negative current set point.
 
+If the Thermostat is used for temperature control with the Sinara 5432 DAC "Zotino", and is connected via an IDC cable, the TEC polarity may need to be reversed with the `output <ch> polarity reversed` TCP command.
+
 Testing heat flow direction with a low set current is recommended before installation of the TEC module.
 
 ### Limits
 
-Each of the MAX1968 TEC driver has analog/PWM inputs for setting
+Each MAX1968 TEC driver has analog/PWM inputs for setting
 output limits.
 
-Use the `pwm` command to see current settings and maximum values.
+Use the `output` command to see current settings and maximum values.
 
 | Limit       | Unit    | Description                   |
 | ---         | :---:   | ---                           |
@@ -204,28 +203,28 @@ Use the `pwm` command to see current settings and maximum values.
 
 Example: set the maximum voltage of channel 0 to 1.5 V.
 ```
-pwm 0 max_v 1.5
+output 0 max_v 1.5
 ```
 
 Example: set the maximum negative current of channel 0 to -3 A.
 ```
-pwm 0 max_i_neg 3
+output 0 max_i_neg 3
 ```
 
 Example: set the maximum positive current of channel 1 to 3 A.
 ```
-pwm 0 max_i_pos 3
+output 0 max_i_pos 3
 ```
 
 ### Open-loop mode
 
-To manually control TEC output current, omit the limit parameter of
-the `pwm` command. Doing so will disengage the PID control for that
+To manually control TEC output current, set a fixed output current with
+the `output` command. Doing so will disengage the PID control for that
 channel.
 
 Example: set output current of channel 0 to 0 A.
 ```
-pwm 0 i_set 0
+output 0 i_set 0
 ```
 
 ## PID-stabilized temperature control
@@ -238,7 +237,7 @@ pid 0 target 20
 Enter closed-loop mode by switching control of the TEC output current
 of channel 0 to the PID algorithm:
 ```
-pwm 0 pid
+output 0 pid
 ```
 
 ## LED indicators
@@ -251,14 +250,14 @@ pwm 0 pid
 
 ## Reports
 
-Use the bare `report` command to obtain a single report. Enable
-continuous reporting with `report mode on`. Reports are JSON objects
+Use the bare `report` command to obtain a single report. Reports are JSON objects
 with the following keys.
 
 | Key            | Unit            | Description                                          |
 | ---            | :---:           | ---                                                  |
 | `channel`      | Integer         | Channel `0`, or `1`                                  |
 | `time`         | Seconds         | Temperature measurement time                         |
+| `interval`     | Seconds         | Time elapsed since last report update on channel     |
 | `adc`          | Volts           | AD7172 input                                         |
 | `sens`         | Ohms            | Thermistor resistance derived from `adc`             |
 | `temperature`  | Degrees Celsius | Steinhart-Hart conversion result derived from `sens` |
@@ -271,7 +270,7 @@ with the following keys.
 | `tec_u_meas`   | Volts           | Measurement of the voltage across the TEC            |
 | `pid_output`   | Amperes         | PID control output                                   |
 
-Note: With Thermostat v2 and below, the voltage and current readouts `i_tec` and `tec_i` are noisy without the hardware fix shown in [this PR][https://git.m-labs.hk/M-Labs/thermostat/pulls/105].
+Note: Prior to Thermostat hardware revision v2.2.4, the voltage and current readouts `i_tec` and `tec_i` are noisy without the hardware fix shown in [this PR](https://git.m-labs.hk/M-Labs/thermostat/pulls/105).
 
 ## PID Tuning
 

flake.nix

@@ -63,7 +63,7 @@
         name = "thermostat-dev-shell";
         packages = with pkgs; [
           rust llvm
-          openocd dfu-util
+          openocd dfu-util rlwrap
           ] ++ (with python3Packages; [
             numpy matplotlib
           ]);

pytec/autotune.py

@@ -253,9 +253,9 @@ def main():
 
         tuner_out = tuner.output()
 
-        tec.set_param("pwm", channel, "i_set", tuner_out)
+        tec.set_param("output", channel, "i_set", tuner_out)
 
-    tec.set_param("pwm", channel, "i_set", 0)
+    tec.set_param("output", channel, "i_set", 0)
 
 
 if __name__ == "__main__":

pytec/example.py

@@ -2,9 +2,9 @@ from pytec.client import Client
 
 tec = Client() #(host="localhost", port=6667)
 tec.set_param("s-h", 1, "t0", 20)
-print(tec.get_pwm())
+print(tec.get_output())
 print(tec.get_pid())
-print(tec.get_pwm())
+print(tec.get_output())
 print(tec.get_postfilter())
 print(tec.get_steinhart_hart())
 for data in tec.report_mode():

pytec/pytec/client.py

@@ -1,6 +1,7 @@
 import socket
 import json
 import logging
+import time
 
 class CommandError(Exception):
     pass
@@ -12,11 +13,11 @@ class Client:
         self._check_zero_limits()
 
     def _check_zero_limits(self):
-        pwm_report = self.get_pwm()
-        for pwm_channel in pwm_report:
+        output_report = self.get_output()
+        for output_channel in output_report:
             for limit in ["max_i_neg", "max_i_pos", "max_v"]:
-                if pwm_channel[limit]["value"] == 0.0:
-                    logging.warning("`{}` limit is set to zero on channel {}".format(limit, pwm_channel["channel"]))
+                if output_channel[limit] == 0.0:
+                    logging.warning("`{}` limit is set to zero on channel {}".format(limit, output_channel["channel"]))
 
     def _read_line(self):
         # read more lines
@@ -46,25 +47,27 @@ class Client:
             result[int(item["channel"])] = item
         return result
 
-    def get_pwm(self):
-        """Retrieve PWM limits for the TEC
+    def get_output(self):
+        """Retrieve output limits for the TEC
 
         Example::
             [{'channel': 0,
               'center': 'vref',
-              'i_set': {'max': 2.9802790335151985, 'value': -0.02002179650216762},
-              'max_i_neg': {'max': 3.0, 'value': 3.0},
-              'max_v': {'max': 5.988, 'value': 5.988},
-              'max_i_pos': {'max': 3.0, 'value': 3.0}},
+              'i_set': -0.02002179650216762,
+              'max_i_neg': 2.0,
+              'max_v': 3.988,
+              'max_i_pos': 2.0,
+              'polarity': 'normal',
              {'channel': 1,
               'center': 'vref',
-              'i_set': {'max': 2.9802790335151985, 'value': -0.02002179650216762},
-              'max_i_neg': {'max': 3.0, 'value': 3.0},
-              'max_v': {'max': 5.988, 'value': 5.988},
-              'max_i_pos': {'max': 3.0, 'value': 3.0}}
+              'i_set': -0.02002179650216762,
+              'max_i_neg': 2.0,
+              'max_v': 3.988,
+              'max_i_pos': 2.0}
+              'polarity': 'normal',
             ]
         """
-        return self._get_conf("pwm")
+        return self._get_conf("output")
 
     def get_pid(self):
         """Retrieve PID control state
@@ -126,9 +129,8 @@ class Client:
              'tec_u_meas': 2.5340000000000003,
              'pid_output': 2.067581958092247}
         """
-        self._command("report mode", "on")
-
         while True:
+            self._socket.sendall("report\n".encode('utf-8'))
             line = self._read_line()
             if not line:
                 break
@@ -136,12 +138,13 @@ class Client:
                 yield json.loads(line)
             except json.decoder.JSONDecodeError:
                 pass
+            time.sleep(0.05)
 
     def set_param(self, topic, channel, field="", value=""):
         """Set configuration parameters
 
         Examples::
-            tec.set_param("pwm", 0, "max_v", 2.0)
+            tec.set_param("output", 0, "max_v", 2.0)
             tec.set_param("pid", 1, "output_max", 2.5)
             tec.set_param("s-h", 0, "t0", 20.0)
             tec.set_param("center", 0, "vref")
@@ -158,7 +161,7 @@ class Client:
     def power_up(self, channel, target):
         """Start closed-loop mode"""
         self.set_param("pid", channel, "target", value=target)
-        self.set_param("pwm", channel, "pid")
+        self.set_param("output", channel, "pid")
 
     def save_config(self):
         """Save current configuration to EEPROM"""

src/ad5680.rs

@@ -1,12 +1,9 @@
-use stm32f4xx_hal::{
-    hal::{
-        blocking::spi::Transfer,
-        digital::v2::OutputPin,
-    },
-    time::MegaHertz,
-    spi,
-};
 use crate::timer::sleep;
+use stm32f4xx_hal::{
+    hal::{blocking::spi::Transfer, digital::v2::OutputPin},
+    spi,
+    time::MegaHertz,
+};
 
 /// SPI Mode 1
 pub const SPI_MODE: spi::Mode = spi::Mode {
@@ -27,11 +24,8 @@ pub struct Dac<SPI: Transfer<u8>, S: OutputPin> {
 impl<SPI: Transfer<u8>, S: OutputPin> Dac<SPI, S> {
     pub fn new(spi: SPI, mut sync: S) -> Self {
         let _ = sync.set_low();
-        
-        Dac {
-            spi,
-            sync,
-        }
+
+        Dac { spi, sync }
     }
 
     fn write(&mut self, buf: &mut [u8]) -> Result<(), SPI::Error> {
@@ -47,11 +41,7 @@ impl<SPI: Transfer<u8>, S: OutputPin> Dac<SPI, S> {
 
     pub fn set(&mut self, value: u32) -> Result<u32, SPI::Error> {
         let value = value.min(MAX_VALUE);
-        let mut buf = [
-            (value >> 14) as u8,
-            (value >> 6) as u8,
-            (value << 2) as u8,
-        ];
+        let mut buf = [(value >> 14) as u8, (value >> 6) as u8, (value << 2) as u8];
         self.write(&mut buf)?;
         Ok(value)
     }

src/ad7172/adc.rs

@@ -1,18 +1,12 @@
+use super::{
+    checksum::{Checksum, ChecksumMode},
+    regs::{self, Register, RegisterData},
+    DigitalFilterOrder, Input, Mode, PostFilter, RefSource,
+};
 use core::fmt;
 use log::{info, warn};
-use stm32f4xx_hal::hal::{
-    blocking::spi::Transfer,
-    digital::v2::OutputPin,
-};
-use uom::si::{
-    f64::ElectricPotential,
-    electric_potential::volt,
-};
-use super::{
-    regs::{self, Register, RegisterData},
-    checksum::{ChecksumMode, Checksum},
-    Mode, Input, RefSource, PostFilter, DigitalFilterOrder,
-};
+use stm32f4xx_hal::hal::{blocking::spi::Transfer, digital::v2::OutputPin};
+use uom::si::{electric_potential::volt, f64::ElectricPotential};
 
 /// AD7172-2 implementation
 ///
@@ -27,7 +21,8 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
     pub fn new(spi: SPI, mut nss: NSS) -> Result<Self, SPI::Error> {
         let _ = nss.set_high();
         let mut adc = Adc {
-            spi, nss,
+            spi,
+            nss,
             checksum_mode: ChecksumMode::Off,
         };
         adc.reset()?;
@@ -55,8 +50,7 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
 
     /// `0x00DX` for AD7172-2
     pub fn identify(&mut self) -> Result<u16, SPI::Error> {
-        self.read_reg(&regs::Id)
-            .map(|id| id.id())
+        self.read_reg(&regs::Id).map(|id| id.id())
     }
 
     pub fn set_checksum_mode(&mut self, mode: ChecksumMode) -> Result<(), SPI::Error> {
@@ -76,7 +70,10 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
     }
 
     pub fn setup_channel(
-        &mut self, index: u8, in_pos: Input, in_neg: Input
+        &mut self,
+        index: u8,
+        in_pos: Input,
+        in_neg: Input,
     ) -> Result<(), SPI::Error> {
         self.update_reg(&regs::SetupCon { index }, |data| {
             data.set_bipolar(false);
@@ -106,7 +103,11 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
         let offset = self.read_reg(&regs::Offset { index })?.offset();
         let gain = self.read_reg(&regs::Gain { index })?.gain();
         let bipolar = self.read_reg(&regs::SetupCon { index })?.bipolar();
-        Ok(ChannelCalibration { offset, gain, bipolar })
+        Ok(ChannelCalibration {
+            offset,
+            gain,
+            bipolar,
+        })
     }
 
     pub fn start_continuous_conversion(&mut self) -> Result<(), SPI::Error> {
@@ -119,44 +120,43 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
     }
 
     pub fn get_postfilter(&mut self, index: u8) -> Result<Option<PostFilter>, SPI::Error> {
-        self.read_reg(&regs::FiltCon { index })
-            .map(|data| {
-                if data.enh_filt_en() {
-                    Some(data.enh_filt())
-                } else {
-                    None
-                }
-            })
+        self.read_reg(&regs::FiltCon { index }).map(|data| {
+            if data.enh_filt_en() {
+                Some(data.enh_filt())
+            } else {
+                None
+            }
+        })
     }
 
-    pub fn set_postfilter(&mut self, index: u8, filter: Option<PostFilter>) -> Result<(), SPI::Error> {
-        self.update_reg(&regs::FiltCon { index }, |data| {
-            match filter {
-                None => data.set_enh_filt_en(false),
-                Some(filter) => {
-                    data.set_enh_filt_en(true);
-                    data.set_enh_filt(filter);
-                }
+    pub fn set_postfilter(
+        &mut self,
+        index: u8,
+        filter: Option<PostFilter>,
+    ) -> Result<(), SPI::Error> {
+        self.update_reg(&regs::FiltCon { index }, |data| match filter {
+            None => data.set_enh_filt_en(false),
+            Some(filter) => {
+                data.set_enh_filt_en(true);
+                data.set_enh_filt(filter);
             }
         })
     }
 
     /// Returns the channel the data is from
     pub fn data_ready(&mut self) -> Result<Option<u8>, SPI::Error> {
-        self.read_reg(&regs::Status)
-            .map(|status| {
-                if status.ready() {
-                    Some(status.channel())
-                } else {
-                    None
-                }
-            })
+        self.read_reg(&regs::Status).map(|status| {
+            if status.ready() {
+                Some(status.channel())
+            } else {
+                None
+            }
+        })
     }
 
     /// Get data
     pub fn read_data(&mut self) -> Result<u32, SPI::Error> {
-        self.read_reg(&regs::Data)
-            .map(|data| data.data())
+        self.read_reg(&regs::Data).map(|data| data.data())
     }
 
     fn read_reg<R: regs::Register>(&mut self, reg: &R) -> Result<R::Data, SPI::Error> {
@@ -175,12 +175,21 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
                 break;
             }
             // Retry
-            warn!("read_reg {:02X}: checksum error: {:?}!={:?}, retrying", reg.address(), checksum_expected, checksum_in);
+            warn!(
+                "read_reg {:02X}: checksum error: {:?}!={:?}, retrying",
+                reg.address(),
+                checksum_expected,
+                checksum_in
+            );
         }
         Ok(reg_data)
     }
 
-    fn write_reg<R: regs::Register>(&mut self, reg: &R, reg_data: &mut R::Data) -> Result<(), SPI::Error> {
+    fn write_reg<R: regs::Register>(
+        &mut self,
+        reg: &R,
+        reg_data: &mut R::Data,
+    ) -> Result<(), SPI::Error> {
         loop {
             let address = reg.address();
             let mut checksum = Checksum::new(match self.checksum_mode {
@@ -190,7 +199,7 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
                 ChecksumMode::Crc => ChecksumMode::Crc,
             });
             checksum.feed(&[address]);
-            checksum.feed(&reg_data);
+            checksum.feed(reg_data);
             let checksum_out = checksum.result();
 
             let mut data = reg_data.clone();
@@ -201,7 +210,10 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
             if *readback_data == **reg_data {
                 return Ok(());
             }
-            warn!("write_reg {:02X}: readback error, {:?}!={:?}, retrying", address, &*readback_data, &**reg_data);
+            warn!(
+                "write_reg {:02X}: readback error, {:?}!={:?}, retrying",
+                address, &*readback_data, &**reg_data
+            );
         }
     }
 
@@ -225,7 +237,12 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
         Ok(())
     }
 
-    fn transfer<'w>(&mut self, addr: u8, reg_data: &'w mut [u8], checksum: Option<u8>) -> Result<Option<u8>, SPI::Error> {
+    fn transfer(
+        &mut self,
+        addr: u8,
+        reg_data: &mut [u8],
+        checksum: Option<u8>,
+    ) -> Result<Option<u8>, SPI::Error> {
         let mut addr_buf = [addr];
 
         let _ = self.nss.set_low();
@@ -234,8 +251,7 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
             Err(e) => Err(e),
         };
         let result = match (result, checksum) {
-            (Ok(_), None) =>
-                Ok(None),
+            (Ok(_), None) => Ok(None),
             (Ok(_), Some(checksum_out)) => {
                 let mut checksum_buf = [checksum_out; 1];
                 match self.spi.transfer(&mut checksum_buf) {
@@ -243,8 +259,7 @@ impl<SPI: Transfer<u8, Error = E>, NSS: OutputPin, E: fmt::Debug> Adc<SPI, NSS>
                     Err(e) => Err(e),
                 }
             }
-            (Err(e), _) =>
-                Err(e),
+            (Err(e), _) => Err(e),
         };
         let _ = self.nss.set_high();
 

src/ad7172/checksum.rs

@@ -29,13 +29,13 @@ impl Checksum {
 
     fn feed_byte(&mut self, input: u8) {
         match self.mode {
-            ChecksumMode::Off => {},
+            ChecksumMode::Off => {}
             ChecksumMode::Xor => self.state ^= input,
             ChecksumMode::Crc => {
                 for i in 0..8 {
                     let input_mask = 0x80 >> i;
-                    self.state = (self.state << 1) ^
-                        if ((self.state & 0x80) != 0) != ((input & input_mask) != 0) {
+                    self.state = (self.state << 1)
+                        ^ if ((self.state & 0x80) != 0) != ((input & input_mask) != 0) {
                             0x07 /* x8 + x2 + x + 1 */
                         } else {
                             0
@@ -54,7 +54,7 @@ impl Checksum {
     pub fn result(&self) -> Option<u8> {
         match self.mode {
             ChecksumMode::Off => None,
-            _ => Some(self.state)
+            _ => Some(self.state),
         }
     }
 }

src/ad7172/mod.rs

@@ -1,13 +1,10 @@
 use core::fmt;
 use num_traits::float::Float;
-use serde::{Serialize, Deserialize};
-use stm32f4xx_hal::{
-    time::MegaHertz,
-    spi,
-};
+use serde::{Deserialize, Serialize};
+use stm32f4xx_hal::{spi, time::MegaHertz};
 
-pub mod regs;
 mod checksum;
+pub mod regs;
 pub use checksum::ChecksumMode;
 mod adc;
 pub use adc::*;
@@ -22,7 +19,6 @@ pub const SPI_CLOCK: MegaHertz = MegaHertz(2);
 
 pub const MAX_VALUE: u32 = 0xFF_FFFF;
 
-
 #[derive(Clone, Copy, Debug)]
 #[repr(u8)]
 pub enum Mode {
@@ -105,7 +101,8 @@ impl fmt::Display for Input {
             RefPos => "ref+",
             RefNeg => "ref-",
             _ => "<INVALID>",
-        }.fmt(fmt)
+        }
+        .fmt(fmt)
     }
 }
 
@@ -141,7 +138,8 @@ impl fmt::Display for RefSource {
             Internal => "internal",
             Avdd1MinusAvss => "avdd1-avss",
             _ => "<INVALID>",
-        }.fmt(fmt)
+        }
+        .fmt(fmt)
     }
 }
 

src/ad7172/regs.rs

@@ -1,6 +1,6 @@
-use core::ops::{Deref, DerefMut};
-use byteorder::{BigEndian, ByteOrder};
 use bit_field::BitField;
+use byteorder::{BigEndian, ByteOrder};
+use core::ops::{Deref, DerefMut};
 
 use super::*;
 
@@ -9,7 +9,7 @@ pub trait Register {
     fn address(&self) -> u8;
 }
 
-pub trait RegisterData: Clone + Deref<Target=[u8]> + DerefMut {
+pub trait RegisterData: Clone + Deref<Target = [u8]> + DerefMut {
     fn empty() -> Self;
 }
 
@@ -49,7 +49,9 @@ macro_rules! def_reg {
         }
     };
     ($Reg: ident, u8, $reg: ident, $addr: expr, $size: expr) => {
-        pub struct $Reg { pub index: u8, }
+        pub struct $Reg {
+            pub index: u8,
+        }
         impl Register for $Reg {
             type Data = $reg::Data;
             fn address(&self) -> u8 {
@@ -76,7 +78,7 @@ macro_rules! def_reg {
                 }
             }
         }
-    }
+    };
 }
 
 macro_rules! reg_bit {
@@ -146,7 +148,7 @@ def_reg!(Status, status, 0x00, 1);
 impl status::Data {
     /// Is there new data to read?
     pub fn ready(&self) -> bool {
-        ! self.not_ready()
+        !self.not_ready()
     }
 
     reg_bit!(not_ready, 0, 7, "No data ready indicator");
@@ -159,9 +161,21 @@ impl status::Data {
 def_reg!(AdcMode, adc_mode, 0x01, 2);
 impl adc_mode::Data {
     reg_bits!(delay, set_delay, 0, 0..=2, "Delay after channel switch");
-    reg_bit!(sing_cyc, set_sing_cyc, 0, 5, "Can only used with single channel");
+    reg_bit!(
+        sing_cyc,
+        set_sing_cyc,
+        0,
+        5,
+        "Can only used with single channel"
+    );
     reg_bit!(hide_delay, set_hide_delay, 0, 6, "Hide delay");
-    reg_bit!(ref_en, set_ref_en, 0, 7, "Enable internal reference, output buffered 2.5 V to REFOUT");
+    reg_bit!(
+        ref_en,
+        set_ref_en,
+        0,
+        7,
+        "Enable internal reference, output buffered 2.5 V to REFOUT"
+    );
     reg_bits!(clockset, set_clocksel, 1, 2..=3, "Clock source");
     reg_bits!(mode, set_mode, 1, 4..=6, Mode, "Operating mode");
 }
@@ -174,15 +188,19 @@ impl if_mode::Data {
 def_reg!(Data, data, 0x04, 3);
 impl data::Data {
     pub fn data(&self) -> u32 {
-        (u32::from(self.0[0]) << 16) |
-        (u32::from(self.0[1]) << 8) |
-        u32::from(self.0[2])
+        (u32::from(self.0[0]) << 16) | (u32::from(self.0[1]) << 8) | u32::from(self.0[2])
     }
 }
 
 def_reg!(GpioCon, gpio_con, 0x06, 2);
 impl gpio_con::Data {
-    reg_bit!(sync_en, set_sync_en, 0, 3, "Enables the SYNC/ERROR pin as a sync input");
+    reg_bit!(
+        sync_en,
+        set_sync_en,
+        0,
+        3,
+        "Enables the SYNC/ERROR pin as a sync input"
+    );
 }
 
 def_reg!(Id, id, 0x07, 2);
@@ -200,8 +218,7 @@ impl channel::Data {
     /// Which input is connected to positive input of this channel
     #[allow(unused)]
     pub fn a_in_pos(&self) -> Input {
-        ((self.0[0].get_bits(0..=1) << 3) |
-         self.0[1].get_bits(5..=7)).into()
+        ((self.0[0].get_bits(0..=1) << 3) | self.0[1].get_bits(5..=7)).into()
     }
     /// Set which input is connected to positive input of this channel
     #[allow(unused)]
@@ -210,27 +227,66 @@ impl channel::Data {
         self.0[0].set_bits(0..=1, value >> 3);
         self.0[1].set_bits(5..=7, value & 0x7);
     }
-    reg_bits!(a_in_neg, set_a_in_neg, 1, 0..=4, Input,
-              "Which input is connected to negative input of this channel");
+    reg_bits!(
+        a_in_neg,
+        set_a_in_neg,
+        1,
+        0..=4,
+        Input,
+        "Which input is connected to negative input of this channel"
+    );
 }
 
 def_reg!(SetupCon, u8, setup_con, 0x20, 2);
 impl setup_con::Data {
-    reg_bit!(bipolar, set_bipolar, 0, 4, "Unipolar (`false`) or bipolar (`true`) coded output");
+    reg_bit!(
+        bipolar,
+        set_bipolar,
+        0,
+        4,
+        "Unipolar (`false`) or bipolar (`true`) coded output"
+    );
     reg_bit!(refbuf_pos, set_refbuf_pos, 0, 3, "Enable REF+ input buffer");
     reg_bit!(refbuf_neg, set_refbuf_neg, 0, 2, "Enable REF- input buffer");
     reg_bit!(ainbuf_pos, set_ainbuf_pos, 0, 1, "Enable AIN+ input buffer");
     reg_bit!(ainbuf_neg, set_ainbuf_neg, 0, 0, "Enable AIN- input buffer");
     reg_bit!(burnout_en, 1, 7, "enables a 10 µA current source on the positive analog input selected and a 10 µA current sink on the negative analog input selected");
-    reg_bits!(ref_sel, set_ref_sel, 1, 4..=5, RefSource, "Select reference source for conversion");
+    reg_bits!(
+        ref_sel,
+        set_ref_sel,
+        1,
+        4..=5,
+        RefSource,
+        "Select reference source for conversion"
+    );
 }
 
 def_reg!(FiltCon, u8, filt_con, 0x28, 2);
 impl filt_con::Data {
     reg_bit!(sinc3_map, 0, 7, "If set, mapping of filter register changes to directly program the decimation rate of the sinc3 filter");
-    reg_bit!(enh_filt_en, set_enh_filt_en, 0, 3, "Enable postfilters for enhanced 50Hz and 60Hz rejection");
-    reg_bits!(enh_filt, set_enh_filt, 0, 0..=2, PostFilter, "Select postfilters for enhanced 50Hz and 60Hz rejection");
-    reg_bits!(order, set_order, 1, 5..=6, DigitalFilterOrder, "order of the digital filter that processes the modulator data");
+    reg_bit!(
+        enh_filt_en,
+        set_enh_filt_en,
+        0,
+        3,
+        "Enable postfilters for enhanced 50Hz and 60Hz rejection"
+    );
+    reg_bits!(
+        enh_filt,
+        set_enh_filt,
+        0,
+        0..=2,
+        PostFilter,
+        "Select postfilters for enhanced 50Hz and 60Hz rejection"
+    );
+    reg_bits!(
+        order,
+        set_order,
+        1,
+        5..=6,
+        DigitalFilterOrder,
+        "order of the digital filter that processes the modulator data"
+    );
     reg_bits!(odr, set_odr, 1, 0..=4, "Output data rate");
 }
 
@@ -238,9 +294,7 @@ def_reg!(Offset, u8, offset, 0x30, 3);
 impl offset::Data {
     #[allow(unused)]
     pub fn offset(&self) -> u32 {
-        (u32::from(self.0[0]) << 16) |
-        (u32::from(self.0[1]) << 8) |
-        u32::from(self.0[2])
+        (u32::from(self.0[0]) << 16) | (u32::from(self.0[1]) << 8) | u32::from(self.0[2])
     }
     #[allow(unused)]
     pub fn set_offset(&mut self, value: u32) {
@@ -254,9 +308,7 @@ def_reg!(Gain, u8, gain, 0x38, 3);
 impl gain::Data {
     #[allow(unused)]
     pub fn gain(&self) -> u32 {
-        (u32::from(self.0[0]) << 16) |
-        (u32::from(self.0[1]) << 8) |
-        u32::from(self.0[2])
+        (u32::from(self.0[0]) << 16) | (u32::from(self.0[1]) << 8) | u32::from(self.0[2])
     }
     #[allow(unused)]
     pub fn set_gain(&mut self, value: u32) {

src/channel.rs

@@ -1,14 +1,10 @@
-use stm32f4xx_hal::hal::digital::v2::OutputPin;
-use uom::si::{
-    f64::ElectricPotential,
-    electric_potential::volt,
-};
 use crate::{
-    ad5680,
-    ad7172,
+    ad5680, ad7172,
     channel_state::ChannelState,
-    pins::{ChannelPins, ChannelPinSet},
+    pins::{ChannelPinSet, ChannelPins},
 };
+use stm32f4xx_hal::hal::digital::v2::OutputPin;
+use uom::si::{electric_potential::volt, f64::ElectricPotential};
 
 /// Marker type for the first channel
 pub struct Channel0;
@@ -24,7 +20,7 @@ pub struct Channel<C: ChannelPins> {
     pub vref_meas: ElectricPotential,
     pub shdn: C::Shdn,
     pub vref_pin: C::VRefPin,
-    pub itec_pin: C::ItecPin,
+    pub itec_pin: C::ITecPin,
     /// feedback from `dac` output
     pub dac_feedback_pin: C::DacFeedbackPin,
     pub tec_u_meas_pin: C::TecUMeasPin,
@@ -40,7 +36,8 @@ impl<C: ChannelPins> Channel<C> {
 
         Channel {
             state,
-            dac, vref_meas,
+            dac,
+            vref_meas,
             shdn: pins.shdn,
             vref_pin: pins.vref_pin,
             itec_pin: pins.itec_pin,

src/channel_state.rs

@@ -1,23 +1,20 @@
-use smoltcp::time::{Duration, Instant};
-use uom::si::{
-    f64::{
-        ElectricPotential,
-        ElectricCurrent,
-        ElectricalResistance,
-        ThermodynamicTemperature,
-        Time,
-    },
-    electric_potential::volt,
-    electric_current::ampere,
-    electrical_resistance::ohm,
-    thermodynamic_temperature::degree_celsius,
-    time::millisecond,
-};
 use crate::{
     ad7172,
-    pid,
-    steinhart_hart as sh,
-    command_parser::CenterPoint,
+    command_parser::{CenterPoint, Polarity},
+    config::PwmLimits,
+    pid, steinhart_hart as sh,
+};
+use num_traits::Zero;
+use smoltcp::time::{Duration, Instant};
+use uom::si::{
+    electric_current::ampere,
+    electric_potential::volt,
+    electrical_resistance::ohm,
+    f64::{
+        ElectricCurrent, ElectricPotential, ElectricalResistance, ThermodynamicTemperature, Time,
+    },
+    thermodynamic_temperature::degree_celsius,
+    time::millisecond,
 };
 
 const R_INNER: f64 = 2.0 * 5100.0;
@@ -32,9 +29,11 @@ pub struct ChannelState {
     pub center: CenterPoint,
     pub dac_value: ElectricPotential,
     pub i_set: ElectricCurrent,
+    pub pwm_limits: PwmLimits,
     pub pid_engaged: bool,
     pub pid: pid::Controller,
     pub sh: sh::Parameters,
+    pub polarity: Polarity,
 }
 
 impl ChannelState {
@@ -45,12 +44,18 @@ impl ChannelState {
             adc_time: Instant::from_secs(0),
             // default: 10 Hz
             adc_interval: Duration::from_millis(100),
-            center: CenterPoint::Vref,
+            center: CenterPoint::VRef,
             dac_value: ElectricPotential::new::<volt>(0.0),
             i_set: ElectricCurrent::new::<ampere>(0.0),
+            pwm_limits: PwmLimits {
+                max_v: ElectricPotential::zero(),
+                max_i_pos: ElectricCurrent::zero(),
+                max_i_neg: ElectricCurrent::zero(),
+            },
             pid_engaged: false,
             pid: pid::Controller::new(pid::Parameters::default()),
             sh: sh::Parameters::default(),
+            polarity: Polarity::Normal,
         }
     }
 
@@ -67,8 +72,7 @@ impl ChannelState {
 
     /// Update PID state on ADC input, calculate new DAC output
     pub fn update_pid(&mut self) -> Option<f64> {
-        let temperature = self.get_temperature()?
-            .get::<degree_celsius>();
+        let temperature = self.get_temperature()?.get::<degree_celsius>();
         let pid_output = self.pid.update(temperature);
         Some(pid_output)
     }

src/channels.rs

@@ -1,3 +1,13 @@
+use crate::timer::sleep;
+use crate::{
+    ad5680, ad7172,
+    channel::{Channel, Channel0, Channel1},
+    channel_state::ChannelState,
+    command_handler::JsonBuffer,
+    command_parser::{CenterPoint, Polarity, PwmPin},
+    pins::{self, Channel0VRef, Channel1VRef},
+    steinhart_hart,
+};
 use core::marker::PhantomData;
 use heapless::{consts::U2, Vec};
 use num_traits::Zero;
@@ -5,26 +15,16 @@ use serde::{Serialize, Serializer};
 use smoltcp::time::Instant;
 use stm32f4xx_hal::hal;
 use uom::si::{
-    f64::{ElectricCurrent, ElectricPotential, ElectricalResistance, Time},
-    electric_potential::{millivolt, volt},
     electric_current::ampere,
+    electric_potential::{millivolt, volt},
     electrical_resistance::ohm,
+    f64::{ElectricCurrent, ElectricPotential, ElectricalResistance, Time},
     ratio::ratio,
     thermodynamic_temperature::degree_celsius,
 };
-use crate::{
-    ad5680,
-    ad7172,
-    channel::{Channel, Channel0, Channel1},
-    channel_state::ChannelState,
-    command_parser::{CenterPoint, PwmPin},
-    command_handler::JsonBuffer,
-    pins::{self, Channel0VRef, Channel1VRef},
-    steinhart_hart,
-};
 
 pub enum PinsAdcReadTarget {
-    VREF,
+    VRef,
     DacVfb,
     ITec,
     VTec,
@@ -44,7 +44,11 @@ pub const MAX_TEC_V: ElectricPotential = ElectricPotential {
     units: PhantomData,
     value: 4.0,
 };
-
+const MAX_TEC_I_DUTY_TO_CURRENT_RATE: ElectricCurrent = ElectricCurrent {
+    dimension: PhantomData,
+    units: PhantomData,
+    value: 1.0 / (10.0 * R_SENSE / 3.3),
+};
 // DAC chip outputs 0-5v, which is then passed through a resistor dividor to provide 0-3v range
 const DAC_OUT_V_MAX: ElectricPotential = ElectricPotential {
     dimension: PhantomData,
@@ -68,19 +72,25 @@ impl Channels {
         adc.set_sync_enable(false).unwrap();
 
         // Setup channels and start ADC
-        adc.setup_channel(0, ad7172::Input::Ain2, ad7172::Input::Ain3).unwrap();
-        let adc_calibration0 = adc.get_calibration(0)
-            .expect("adc_calibration0");
-        adc.setup_channel(1, ad7172::Input::Ain0, ad7172::Input::Ain1).unwrap();
-        let adc_calibration1 = adc.get_calibration(1)
-            .expect("adc_calibration1");
+        adc.setup_channel(0, ad7172::Input::Ain2, ad7172::Input::Ain3)
+            .unwrap();
+        let adc_calibration0 = adc.get_calibration(0).expect("adc_calibration0");
+        adc.setup_channel(1, ad7172::Input::Ain0, ad7172::Input::Ain1)
+            .unwrap();
+        let adc_calibration1 = adc.get_calibration(1).expect("adc_calibration1");
         adc.start_continuous_conversion().unwrap();
 
         let channel0 = Channel::new(pins.channel0, adc_calibration0);
         let channel1 = Channel::new(pins.channel1, adc_calibration1);
         let pins_adc = pins.pins_adc;
         let pwm = pins.pwm;
-        let mut channels = Channels { channel0, channel1, adc, pins_adc, pwm };
+        let mut channels = Channels {
+            channel0,
+            channel1,
+            adc,
+            pins_adc,
+            pwm,
+        };
         for channel in 0..CHANNELS {
             channels.calibrate_dac_value(channel);
             channels.set_i(channel, ElectricCurrent::new::<ampere>(0.0));
@@ -121,10 +131,10 @@ impl Channels {
     /// calculate the TEC i_set centerpoint
     pub fn get_center(&mut self, channel: usize) -> ElectricPotential {
         match self.channel_state(channel).center {
-            CenterPoint::Vref =>
-                self.adc_read(channel, PinsAdcReadTarget::VREF, 8),
-            CenterPoint::Override(center_point) =>
-                ElectricPotential::new::<volt>(center_point.into()),
+            CenterPoint::VRef => self.adc_read(channel, PinsAdcReadTarget::VRef, 8),
+            CenterPoint::Override(center_point) => {
+                ElectricPotential::new::<volt>(center_point.into())
+            }
         }
     }
 
@@ -134,14 +144,14 @@ impl Channels {
         voltage
     }
 
-    pub fn get_i(&mut self, channel: usize) -> ElectricCurrent {
+    pub fn get_i_set(&mut self, channel: usize) -> ElectricCurrent {
         let i_set = self.channel_state(channel).i_set;
         i_set
     }
 
     /// i_set DAC
     fn set_dac(&mut self, channel: usize, voltage: ElectricPotential) -> ElectricPotential {
-        let value = ((voltage / DAC_OUT_V_MAX).get::<ratio>() * (ad5680::MAX_VALUE as f64)) as u32 ;
+        let value = ((voltage / DAC_OUT_V_MAX).get::<ratio>() * (ad5680::MAX_VALUE as f64)) as u32;
         match channel {
             0 => self.channel0.dac.set(value).unwrap(),
             1 => self.channel1.dac.set(value).unwrap(),
@@ -153,64 +163,71 @@ impl Channels {
 
     pub fn set_i(&mut self, channel: usize, i_set: ElectricCurrent) -> ElectricCurrent {
         let i_set = i_set.min(MAX_TEC_I).max(-MAX_TEC_I);
-        let vref_meas = match channel.into() {
+        self.channel_state(channel).i_set = i_set;
+        let negate = match self.channel_state(channel).polarity {
+            Polarity::Normal => 1.0,
+            Polarity::Reversed => -1.0,
+        };
+        let vref_meas = match channel {
             0 => self.channel0.vref_meas,
             1 => self.channel1.vref_meas,
             _ => unreachable!(),
         };
         let center_point = vref_meas;
         let r_sense = ElectricalResistance::new::<ohm>(R_SENSE);
-        let voltage = i_set * 10.0 * r_sense + center_point;
+        let voltage = negate * i_set * 10.0 * r_sense + center_point;
         let voltage = self.set_dac(channel, voltage);
-        let i_set = (voltage - center_point) / (10.0 * r_sense);
-        self.channel_state(channel).i_set = i_set;
-        i_set
+
+        negate * (voltage - center_point) / (10.0 * r_sense)
     }
 
     /// AN4073: ADC Reading Dispersion can be reduced through Averaging
-    pub fn adc_read(&mut self, channel: usize, adc_read_target: PinsAdcReadTarget, avg_pt: u16) -> ElectricPotential {
+    pub fn adc_read(
+        &mut self,
+        channel: usize,
+        adc_read_target: PinsAdcReadTarget,
+        avg_pt: u16,
+    ) -> ElectricPotential {
         let mut sample: u32 = 0;
         match channel {
             0 => {
                 sample = match adc_read_target {
-                    PinsAdcReadTarget::VREF => {
-                        match &self.channel0.vref_pin {
-                            Channel0VRef::Analog(vref_pin) => {
-                                for _ in (0..avg_pt).rev() {
-                                    sample += self
-                                        .pins_adc
-                                        .convert(vref_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                        as u32;
-                                }
-                                sample / avg_pt as u32
-                            },
-                            Channel0VRef::Disabled(_) => {2048 as u32}
+                    PinsAdcReadTarget::VRef => match &self.channel0.vref_pin {
+                        Channel0VRef::Analog(vref_pin) => {
+                            for _ in (0..avg_pt).rev() {
+                                sample += self.pins_adc.convert(
+                                    vref_pin,
+                                    stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                                ) as u32;
+                            }
+                            sample / avg_pt as u32
                         }
-                    }
+                        Channel0VRef::Disabled(_) => 2048_u32,
+                    },
                     PinsAdcReadTarget::DacVfb => {
                         for _ in (0..avg_pt).rev() {
-                            sample += self
-                                .pins_adc
-                                .convert(&self.channel0.dac_feedback_pin,stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                as u32;
+                            sample += self.pins_adc.convert(
+                                &self.channel0.dac_feedback_pin,
+                                stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                            ) as u32;
                         }
                         sample / avg_pt as u32
                     }
                     PinsAdcReadTarget::ITec => {
                         for _ in (0..avg_pt).rev() {
-                            sample += self
-                                .pins_adc
-                                .convert(&self.channel0.itec_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                as u32;
+                            sample += self.pins_adc.convert(
+                                &self.channel0.itec_pin,
+                                stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                            ) as u32;
                         }
                         sample / avg_pt as u32
                     }
                     PinsAdcReadTarget::VTec => {
                         for _ in (0..avg_pt).rev() {
-                            sample += self
-                                .pins_adc
-                                .convert(&self.channel0.tec_u_meas_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                as u32;
+                            sample += self.pins_adc.convert(
+                                &self.channel0.tec_u_meas_pin,
+                                stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                            ) as u32;
                         }
                         sample / avg_pt as u32
                     }
@@ -220,44 +237,42 @@ impl Channels {
             }
             1 => {
                 sample = match adc_read_target {
-                    PinsAdcReadTarget::VREF => {
-                        match &self.channel1.vref_pin {
-                            Channel1VRef::Analog(vref_pin) => {
-                                for _ in (0..avg_pt).rev() {
-                                    sample += self
-                                        .pins_adc
-                                        .convert(vref_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                        as u32;
-                                }
-                                sample / avg_pt as u32
-                            },
-                            Channel1VRef::Disabled(_) => {2048 as u32}
+                    PinsAdcReadTarget::VRef => match &self.channel1.vref_pin {
+                        Channel1VRef::Analog(vref_pin) => {
+                            for _ in (0..avg_pt).rev() {
+                                sample += self.pins_adc.convert(
+                                    vref_pin,
+                                    stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                                ) as u32;
+                            }
+                            sample / avg_pt as u32
                         }
-                    }
+                        Channel1VRef::Disabled(_) => 2048_u32,
+                    },
                     PinsAdcReadTarget::DacVfb => {
                         for _ in (0..avg_pt).rev() {
-                            sample += self
-                                .pins_adc
-                                .convert(&self.channel1.dac_feedback_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                as u32;
+                            sample += self.pins_adc.convert(
+                                &self.channel1.dac_feedback_pin,
+                                stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                            ) as u32;
                         }
                         sample / avg_pt as u32
                     }
                     PinsAdcReadTarget::ITec => {
                         for _ in (0..avg_pt).rev() {
-                            sample += self
-                                .pins_adc
-                                .convert(&self.channel1.itec_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                as u32;
+                            sample += self.pins_adc.convert(
+                                &self.channel1.itec_pin,
+                                stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                            ) as u32;
                         }
                         sample / avg_pt as u32
                     }
                     PinsAdcReadTarget::VTec => {
                         for _ in (0..avg_pt).rev() {
-                            sample += self
-                                .pins_adc
-                                .convert(&self.channel1.tec_u_meas_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
-                                as u32;
+                            sample += self.pins_adc.convert(
+                                &self.channel1.tec_u_meas_pin,
+                                stm32f4xx_hal::adc::config::SampleTime::Cycles_480,
+                            ) as u32;
                         }
                         sample / avg_pt as u32
                     }
@@ -265,18 +280,7 @@ impl Channels {
                 let mv = self.pins_adc.sample_to_millivolts(sample as u16);
                 ElectricPotential::new::<millivolt>(mv as f64)
             }
-            _ => unreachable!()
-        }
-    }
-
-    pub fn read_dac_feedback_until_stable(&mut self, channel: usize, tolerance: ElectricPotential) -> ElectricPotential {
-        let mut prev = self.adc_read(channel, PinsAdcReadTarget::DacVfb, 1);
-        loop {
-            let current = self.adc_read(channel, PinsAdcReadTarget::DacVfb, 1);
-            if (current - prev).abs() < tolerance {
-                return current;
-            }
-            prev = current;
+            _ => unreachable!(),
         }
     }
 
@@ -284,30 +288,29 @@ impl Channels {
     ///
     /// The thermostat DAC applies a control voltage signal to the CTLI pin of MAX driver chip to control its output current.
     /// The CTLI input signal is centered around VREF of the MAX chip. Applying VREF to CTLI sets the output current to 0.
-    /// 
+    ///
     /// This calibration routine measures the VREF voltage and the DAC output with the STM32 ADC, and uses a breadth-first     
-    /// search to find the DAC setting that will produce a DAC output voltage closest to VREF. This DAC output voltage will 
-    /// be stored and used in subsequent i_set routines to bias the current control signal to the measured VREF, reducing 
+    /// search to find the DAC setting that will produce a DAC output voltage closest to VREF. This DAC output voltage will
+    /// be stored and used in subsequent i_set routines to bias the current control signal to the measured VREF, reducing
     /// the offset error of the current control signal.
     ///
     /// The input offset of the STM32 ADC is eliminated by using the same ADC for the measurements, and by only using the
     /// difference in VREF and DAC output for the calibration.
-    /// 
-    /// This routine should be called only once after boot, repeated reading of the vref signal and changing of the stored 
+    ///
+    /// This routine should be called only once after boot, repeated reading of the vref signal and changing of the stored
     /// VREF measurement can introduce significant noise at the current output, degrading the stabilily performance of the
-    /// thermostat. 
+    /// thermostat.
     pub fn calibrate_dac_value(&mut self, channel: usize) {
         let samples = 50;
         let mut target_voltage = ElectricPotential::new::<volt>(0.0);
         for _ in 0..samples {
-            target_voltage = target_voltage + self.get_center(channel);
+            target_voltage += self.get_center(channel);
         }
-        target_voltage = target_voltage / samples as f64;
+        target_voltage /= samples as f64;
         let mut start_value = 1;
         let mut best_error = ElectricPotential::new::<volt>(100.0);
 
-        for step in (0..18).rev() {
-            let mut prev_value = start_value;
+        for step in (5..18).rev() {
             for value in (start_value..=ad5680::MAX_VALUE).step_by(1 << step) {
                 match channel {
                     0 => {
@@ -318,14 +321,15 @@ impl Channels {
                     }
                     _ => unreachable!(),
                 }
+                sleep(10);
 
-                let dac_feedback = self.read_dac_feedback_until_stable(channel, ElectricPotential::new::<volt>(0.001));
+                let dac_feedback = self.adc_read(channel, PinsAdcReadTarget::DacVfb, 64);
                 let error = target_voltage - dac_feedback;
                 if error < ElectricPotential::new::<volt>(0.0) {
                     break;
                 } else if error < best_error {
                     best_error = error;
-                    start_value = prev_value;
+                    start_value = value;
 
                     let vref = (value as f64 / ad5680::MAX_VALUE as f64) * DAC_OUT_V_MAX;
                     match channel {
@@ -334,8 +338,6 @@ impl Channels {
                         _ => unreachable!(),
                     }
                 }
-
-                prev_value = value;
             }
         }
 
@@ -361,110 +363,114 @@ impl Channels {
         }
     }
 
-    fn get_pwm(&self, channel: usize, pin: PwmPin) -> f64 {
-        fn get<P: hal::PwmPin<Duty=u16>>(pin: &P) -> f64 {
-            let duty = pin.get_duty();
-            let max = pin.get_max_duty();
-            duty as f64 / (max as f64)
-        }
-        match (channel, pin) {
-            (_, PwmPin::ISet) =>
-                panic!("i_set is no pwm pin"),
-            (0, PwmPin::MaxIPos) =>
-                get(&self.pwm.max_i_pos0),
-            (0, PwmPin::MaxINeg) =>
-                get(&self.pwm.max_i_neg0),
-            (0, PwmPin::MaxV) =>
-                get(&self.pwm.max_v0),
-            (1, PwmPin::MaxIPos) =>
-                get(&self.pwm.max_i_pos1),
-            (1, PwmPin::MaxINeg) =>
-                get(&self.pwm.max_i_neg1),
-            (1, PwmPin::MaxV) =>
-                get(&self.pwm.max_v1),
-            _ =>
-                unreachable!(),
-        }
+    pub fn get_max_v(&mut self, channel: usize) -> ElectricPotential {
+        self.channel_state(channel).pwm_limits.max_v
     }
 
-    pub fn get_max_v(&mut self, channel: usize) -> (ElectricPotential, ElectricPotential) {
-        let max = 4.0 * ElectricPotential::new::<volt>(3.3);
-        let duty = self.get_pwm(channel, PwmPin::MaxV);
-        (duty * max, MAX_TEC_V)
+    pub fn get_max_i_pos(&mut self, channel: usize) -> ElectricCurrent {
+        self.channel_state(channel).pwm_limits.max_i_pos
     }
 
-    pub fn get_max_i_pos(&mut self, channel: usize) -> (ElectricCurrent, ElectricCurrent) {
-        let max = ElectricCurrent::new::<ampere>(3.0);
-        let duty = self.get_pwm(channel, PwmPin::MaxIPos);
-        (duty * max, MAX_TEC_I)
-    }
-
-    pub fn get_max_i_neg(&mut self, channel: usize) -> (ElectricCurrent, ElectricCurrent) {
-        let max = ElectricCurrent::new::<ampere>(3.0);
-        let duty = self.get_pwm(channel, PwmPin::MaxINeg);
-        (duty * max, MAX_TEC_I)
+    pub fn get_max_i_neg(&mut self, channel: usize) -> ElectricCurrent {
+        self.channel_state(channel).pwm_limits.max_i_neg
     }
 
     // Get current passing through TEC
     pub fn get_tec_i(&mut self, channel: usize) -> ElectricCurrent {
-        (self.adc_read(channel, PinsAdcReadTarget::ITec, 16) - self.adc_read(channel, PinsAdcReadTarget::VREF, 16)) / ElectricalResistance::new::<ohm>(0.4)
+        let tec_i = (self.adc_read(channel, PinsAdcReadTarget::ITec, 16)
+            - self.adc_read(channel, PinsAdcReadTarget::VRef, 16))
+            / ElectricalResistance::new::<ohm>(0.4);
+        match self.channel_state(channel).polarity {
+            Polarity::Normal => tec_i,
+            Polarity::Reversed => -tec_i,
+        }
     }
 
     // Get voltage across TEC
     pub fn get_tec_v(&mut self, channel: usize) -> ElectricPotential {
-        (self.adc_read(channel, PinsAdcReadTarget::VTec, 16) - ElectricPotential::new::<volt>(1.5)) * 4.0
+        (self.adc_read(channel, PinsAdcReadTarget::VTec, 16) - ElectricPotential::new::<volt>(1.5))
+            * 4.0
     }
 
     fn set_pwm(&mut self, channel: usize, pin: PwmPin, duty: f64) -> f64 {
-        fn set<P: hal::PwmPin<Duty=u16>>(pin: &mut P, duty: f64) -> f64 {
+        fn set<P: hal::PwmPin<Duty = u16>>(pin: &mut P, duty: f64) -> f64 {
             let max = pin.get_max_duty();
             let value = ((duty * (max as f64)) as u16).min(max);
             pin.set_duty(value);
             value as f64 / (max as f64)
         }
         match (channel, pin) {
-            (_, PwmPin::ISet) =>
-                panic!("i_set is no pwm pin"),
-            (0, PwmPin::MaxIPos) =>
-                set(&mut self.pwm.max_i_pos0, duty),
-            (0, PwmPin::MaxINeg) =>
-                set(&mut self.pwm.max_i_neg0, duty),
-            (0, PwmPin::MaxV) =>
-                set(&mut self.pwm.max_v0, duty),
-            (1, PwmPin::MaxIPos) =>
-                set(&mut self.pwm.max_i_pos1, duty),
-            (1, PwmPin::MaxINeg) =>
-                set(&mut self.pwm.max_i_neg1, duty),
-            (1, PwmPin::MaxV) =>
-                set(&mut self.pwm.max_v1, duty),
-            _ =>
-                unreachable!(),
+            (_, PwmPin::ISet) => panic!("i_set is no pwm pin"),
+            (0, PwmPin::MaxIPos) => set(&mut self.pwm.max_i_pos0, duty),
+            (0, PwmPin::MaxINeg) => set(&mut self.pwm.max_i_neg0, duty),
+            (0, PwmPin::MaxV) => set(&mut self.pwm.max_v0, duty),
+            (1, PwmPin::MaxIPos) => set(&mut self.pwm.max_i_pos1, duty),
+            (1, PwmPin::MaxINeg) => set(&mut self.pwm.max_i_neg1, duty),
+            (1, PwmPin::MaxV) => set(&mut self.pwm.max_v1, duty),
+            _ => unreachable!(),
         }
     }
 
-    pub fn set_max_v(&mut self, channel: usize, max_v: ElectricPotential) -> (ElectricPotential, ElectricPotential) {
+    pub fn set_max_v(
+        &mut self,
+        channel: usize,
+        max_v: ElectricPotential,
+    ) -> (ElectricPotential, ElectricPotential) {
         let max = 4.0 * ElectricPotential::new::<volt>(3.3);
-        let duty = (max_v.min(MAX_TEC_V).max(ElectricPotential::zero()) / max).get::<ratio>();
+        let max_v = max_v.min(MAX_TEC_V).max(ElectricPotential::zero());
+        let duty = (max_v / max).get::<ratio>();
         let duty = self.set_pwm(channel, PwmPin::MaxV, duty);
+        self.channel_state(channel).pwm_limits.max_v = max_v;
         (duty * max, max)
     }
 
-    pub fn set_max_i_pos(&mut self, channel: usize, max_i_pos: ElectricCurrent) -> (ElectricCurrent, ElectricCurrent) {
+    pub fn set_max_i_pos(
+        &mut self,
+        channel: usize,
+        max_i_pos: ElectricCurrent,
+    ) -> (ElectricCurrent, ElectricCurrent) {
         let max = ElectricCurrent::new::<ampere>(3.0);
-        let duty = (max_i_pos.min(MAX_TEC_I).max(ElectricCurrent::zero()) / max).get::<ratio>();
-        let duty = self.set_pwm(channel, PwmPin::MaxIPos, duty);
-        (duty * max, max)
+        let max_i_pos = max_i_pos.min(MAX_TEC_I).max(ElectricCurrent::zero());
+        let duty = (max_i_pos / MAX_TEC_I_DUTY_TO_CURRENT_RATE).get::<ratio>();
+        let duty = match self.channel_state(channel).polarity {
+            Polarity::Normal => self.set_pwm(channel, PwmPin::MaxIPos, duty),
+            Polarity::Reversed => self.set_pwm(channel, PwmPin::MaxINeg, duty),
+        };
+        self.channel_state(channel).pwm_limits.max_i_pos = max_i_pos;
+        (duty * MAX_TEC_I_DUTY_TO_CURRENT_RATE, max)
     }
 
-    pub fn set_max_i_neg(&mut self, channel: usize, max_i_neg: ElectricCurrent) -> (ElectricCurrent, ElectricCurrent) {
+    pub fn set_max_i_neg(
+        &mut self,
+        channel: usize,
+        max_i_neg: ElectricCurrent,
+    ) -> (ElectricCurrent, ElectricCurrent) {
         let max = ElectricCurrent::new::<ampere>(3.0);
-        let duty = (max_i_neg.min(MAX_TEC_I).max(ElectricCurrent::zero()) / max).get::<ratio>();
-        let duty = self.set_pwm(channel, PwmPin::MaxINeg, duty);
-        (duty * max, max)
+        let max_i_neg = max_i_neg.min(MAX_TEC_I).max(ElectricCurrent::zero());
+        let duty = (max_i_neg / MAX_TEC_I_DUTY_TO_CURRENT_RATE).get::<ratio>();
+        let duty = match self.channel_state(channel).polarity {
+            Polarity::Normal => self.set_pwm(channel, PwmPin::MaxINeg, duty),
+            Polarity::Reversed => self.set_pwm(channel, PwmPin::MaxIPos, duty),
+        };
+        self.channel_state(channel).pwm_limits.max_i_neg = max_i_neg;
+        (duty * MAX_TEC_I_DUTY_TO_CURRENT_RATE, max)
+    }
+
+    pub fn set_polarity(&mut self, channel: usize, polarity: Polarity) {
+        if self.channel_state(channel).polarity != polarity {
+            let i_set = self.channel_state(channel).i_set;
+            let max_i_pos = self.get_max_i_pos(channel);
+            let max_i_neg = self.get_max_i_neg(channel);
+            self.channel_state(channel).polarity = polarity;
+
+            self.set_i(channel, i_set);
+            self.set_max_i_pos(channel, max_i_pos);
+            self.set_max_i_neg(channel, max_i_neg);
+        }
     }
 
     fn report(&mut self, channel: usize) -> Report {
-        let i_set = self.get_i(channel);
+        let i_set = self.get_i_set(channel);
         let i_tec = self.adc_read(channel, PinsAdcReadTarget::ITec, 16);
         let tec_i = self.get_tec_i(channel);
         let dac_value = self.get_dac(channel);
@@ -476,7 +482,8 @@ impl Channels {
             interval: state.get_adc_interval(),
             adc: state.get_adc(),
             sens: state.get_sens(),
-            temperature: state.get_temperature()
+            temperature: state
+                .get_temperature()
                 .map(|temperature| temperature.get::<degree_celsius>()),
             pid_engaged: state.pid_engaged,
             i_set,
@@ -514,27 +521,31 @@ impl Channels {
         false
     }
 
-    fn pwm_summary(&mut self, channel: usize) -> PwmSummary {
-        PwmSummary {
+    fn output_summary(&mut self, channel: usize) -> OutputSummary {
+        OutputSummary {
             channel,
             center: CenterPointJson(self.channel_state(channel).center.clone()),
-            i_set: (self.get_i(channel), MAX_TEC_I).into(),
-            max_v: self.get_max_v(channel).into(),
-            max_i_pos: self.get_max_i_pos(channel).into(),
-            max_i_neg: self.get_max_i_neg(channel).into(),
+            i_set: self.get_i_set(channel),
+            max_v: self.get_max_v(channel),
+            max_i_pos: self.get_max_i_pos(channel),
+            max_i_neg: self.get_max_i_neg(channel),
+            polarity: PolarityJson(self.channel_state(channel).polarity.clone()),
         }
     }
 
-    pub fn pwm_summaries_json(&mut self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
+    pub fn output_summaries_json(&mut self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
         let mut summaries = Vec::<_, U2>::new();
         for channel in 0..CHANNELS {
-            let _ = summaries.push(self.pwm_summary(channel));
+            let _ = summaries.push(self.output_summary(channel));
         }
         serde_json_core::to_vec(&summaries)
     }
 
     fn postfilter_summary(&mut self, channel: usize) -> PostFilterSummary {
-        let rate = self.adc.get_postfilter(channel as u8).unwrap()
+        let rate = self
+            .adc
+            .get_postfilter(channel as u8)
+            .unwrap()
             .and_then(|filter| filter.output_rate());
         PostFilterSummary { channel, rate }
     }
@@ -552,7 +563,9 @@ impl Channels {
         SteinhartHartSummary { channel, params }
     }
 
-    pub fn steinhart_hart_summaries_json(&mut self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
+    pub fn steinhart_hart_summaries_json(
+        &mut self,
+    ) -> Result<JsonBuffer, serde_json_core::ser::Error> {
         let mut summaries = Vec::<_, U2>::new();
         for channel in 0..CHANNELS {
             let _ = summaries.push(self.steinhart_hart_summary(channel));
@@ -595,34 +608,36 @@ impl Serialize for CenterPointJson {
         S: Serializer,
     {
         match self.0 {
-            CenterPoint::Vref =>
-                serializer.serialize_str("vref"),
-            CenterPoint::Override(vref) =>
-                serializer.serialize_f32(vref),
+            CenterPoint::VRef => serializer.serialize_str("vref"),
+            CenterPoint::Override(vref) => serializer.serialize_f32(vref),
         }
     }
 }
 
-#[derive(Serialize)]
-pub struct PwmSummaryField<T: Serialize> {
-    value: T,
-    max: T,
-}
+pub struct PolarityJson(Polarity);
 
-impl<T: Serialize> From<(T, T)> for PwmSummaryField<T> {
-    fn from((value, max): (T, T)) -> Self {
-        PwmSummaryField { value, max }
+// used in JSON encoding, not for config
+impl Serialize for PolarityJson {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        serializer.serialize_str(match self.0 {
+            Polarity::Normal => "normal",
+            Polarity::Reversed => "reversed",
+        })
     }
 }
 
 #[derive(Serialize)]
-pub struct PwmSummary {
+pub struct OutputSummary {
     channel: usize,
     center: CenterPointJson,
-    i_set: PwmSummaryField<ElectricCurrent>,
-    max_v: PwmSummaryField<ElectricPotential>,
-    max_i_pos: PwmSummaryField<ElectricCurrent>,
-    max_i_neg: PwmSummaryField<ElectricCurrent>,
+    i_set: ElectricCurrent,
+    max_v: ElectricPotential,
+    max_i_pos: ElectricCurrent,
+    max_i_neg: ElectricCurrent,
+    polarity: PolarityJson,
 }
 
 #[derive(Serialize)]

src/command_handler.rs

@@ -1,45 +1,30 @@
-use smoltcp::socket::TcpSocket;
-use log::{error, warn};
-use core::fmt::Write;
-use heapless::{consts::U1024, Vec};
 use super::{
-    net,
-    command_parser::{
-        Ipv4Config, 
-        Command, 
-        ShowCommand, 
-        CenterPoint, 
-        PidParameter, 
-        PwmPin, 
-        ShParameter
-    },
     ad7172,
-    CHANNEL_CONFIG_KEY,
-    channels::{
-        Channels, 
-        CHANNELS
+    channels::{Channels, CHANNELS},
+    command_parser::{
+        CenterPoint, Command, Ipv4Config, PidParameter, Polarity, PwmPin, ShParameter, ShowCommand,
     },
     config::ChannelConfig,
     dfu,
     flash_store::FlashStore,
-    session::Session,
-    FanCtrl,
     hw_rev::HWRev,
+    net, FanCtrl, CHANNEL_CONFIG_KEY,
 };
+use core::fmt::Write;
+use heapless::{consts::U1024, Vec};
+use log::{error, warn};
+use smoltcp::socket::TcpSocket;
 
-use uom::{
-    si::{
-        f64::{
-            ElectricCurrent,
-            ElectricPotential,
-            ElectricalResistance,
-            ThermodynamicTemperature,
-        },
-        electric_current::ampere,
-        electric_potential::volt,
-        electrical_resistance::ohm,
-        thermodynamic_temperature::degree_celsius,
+use uom::si::{
+    electric_current::ampere,
+    electric_potential::volt,
+    electrical_resistance::ohm,
+    f64::{
+        ElectricCurrent, ElectricPotential, ElectricalResistance, TemperatureInterval,
+        ThermodynamicTemperature,
     },
+    temperature_interval::kelvin,
+    thermodynamic_temperature::degree_celsius,
 };
 
 #[derive(Debug, Clone, PartialEq)]
@@ -52,9 +37,9 @@ pub enum Handler {
 
 #[derive(Clone, Debug, PartialEq)]
 pub enum Error {
-    ReportError,
-    PostFilterRateError,
-    FlashError
+    Report,
+    PostFilterRate,
+    Flash,
 }
 
 pub type JsonBuffer = Vec<u8, U1024>;
@@ -66,19 +51,19 @@ fn send_line(socket: &mut TcpSocket, data: &[u8]) -> bool {
         // instead of sending incomplete line
         warn!(
             "TCP socket has only {}/{} needed {}",
-            send_free + 1, socket.send_capacity(), data.len(),
+            send_free + 1,
+            socket.send_capacity(),
+            data.len(),
         );
     } else {
-        match socket.send_slice(&data) {
+        match socket.send_slice(data) {
             Ok(sent) if sent == data.len() => {
                 let _ = socket.send_slice(b"\n");
                 // success
-                return true
+                return true;
             }
-            Ok(sent) =>
-                warn!("sent only {}/{} bytes", sent, data.len()),
-            Err(e) =>
-                error!("error sending line: {:?}", e),
+            Ok(sent) => warn!("sent only {}/{} bytes", sent, data.len()),
+            Err(e) => error!("error sending line: {:?}", e),
         }
     }
     // not success
@@ -86,17 +71,6 @@ fn send_line(socket: &mut TcpSocket, data: &[u8]) -> bool {
 }
 
 impl Handler {
-
-    fn reporting(socket: &mut TcpSocket) -> Result<Handler, Error> {
-        send_line(socket, b"{}");
-        Ok(Handler::Handled)
-    }
-
-    fn show_report_mode(socket: &mut TcpSocket, session: &Session) -> Result<Handler, Error> {
-        let _ = writeln!(socket, "{{ \"report\": {:?} }}", session.reporting());
-        Ok(Handler::Handled)
-    }
-
     fn show_report(socket: &mut TcpSocket, channels: &mut Channels) -> Result<Handler, Error> {
         match channels.reports_json() {
             Ok(buf) => {
@@ -105,7 +79,7 @@ impl Handler {
             Err(e) => {
                 error!("unable to serialize report: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                return Err(Error::ReportError);
+                return Err(Error::Report);
             }
         }
         Ok(Handler::Handled)
@@ -119,27 +93,30 @@ impl Handler {
             Err(e) => {
                 error!("unable to serialize pid summary: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                return Err(Error::ReportError);
+                return Err(Error::Report);
             }
         }
         Ok(Handler::Handled)
     }
 
     fn show_pwm(socket: &mut TcpSocket, channels: &mut Channels) -> Result<Handler, Error> {
-        match channels.pwm_summaries_json() {
+        match channels.output_summaries_json() {
             Ok(buf) => {
                 send_line(socket, &buf);
             }
             Err(e) => {
                 error!("unable to serialize pwm summary: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                return Err(Error::ReportError);
+                return Err(Error::Report);
             }
         }
         Ok(Handler::Handled)
     }
 
-    fn show_steinhart_hart(socket: &mut TcpSocket, channels: &mut Channels) -> Result<Handler, Error> {
+    fn show_steinhart_hart(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+    ) -> Result<Handler, Error> {
         match channels.steinhart_hart_summaries_json() {
             Ok(buf) => {
                 send_line(socket, &buf);
@@ -147,13 +124,13 @@ impl Handler {
             Err(e) => {
                 error!("unable to serialize steinhart-hart summaries: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                return Err(Error::ReportError);
+                return Err(Error::Report);
             }
         }
         Ok(Handler::Handled)
     }
 
-    fn show_post_filter (socket: &mut TcpSocket, channels: &mut Channels) -> Result<Handler, Error> {
+    fn show_post_filter(socket: &mut TcpSocket, channels: &mut Channels) -> Result<Handler, Error> {
         match channels.postfilter_summaries_json() {
             Ok(buf) => {
                 send_line(socket, &buf);
@@ -161,13 +138,13 @@ impl Handler {
             Err(e) => {
                 error!("unable to serialize postfilter summary: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                return Err(Error::ReportError);
+                return Err(Error::Report);
             }
         }
         Ok(Handler::Handled)
     }
 
-    fn show_ipv4 (socket: &mut TcpSocket, ipv4_config: &mut Ipv4Config) -> Result<Handler, Error> {
+    fn show_ipv4(socket: &mut TcpSocket, ipv4_config: &mut Ipv4Config) -> Result<Handler, Error> {
         let (cidr, gateway) = net::split_ipv4_config(ipv4_config.clone());
         let _ = write!(socket, "{{\"addr\":\"{}\"", cidr);
         gateway.map(|gateway| write!(socket, ",\"gateway\":\"{}\"", gateway));
@@ -175,13 +152,34 @@ impl Handler {
         Ok(Handler::Handled)
     }
 
-    fn engage_pid (socket: &mut TcpSocket, channels: &mut Channels, channel: usize) -> Result<Handler, Error> {
+    fn engage_pid(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+    ) -> Result<Handler, Error> {
         channels.channel_state(channel).pid_engaged = true;
         send_line(socket, b"{}");
         Ok(Handler::Handled)
     }
 
-    fn set_pwm (socket: &mut TcpSocket, channels: &mut Channels, channel: usize, pin: PwmPin, value: f64) -> Result<Handler, Error> {
+    fn set_polarity(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+        polarity: Polarity,
+    ) -> Result<Handler, Error> {
+        channels.set_polarity(channel, polarity);
+        send_line(socket, b"{}");
+        Ok(Handler::Handled)
+    }
+
+    fn set_pwm(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+        pin: PwmPin,
+        value: f64,
+    ) -> Result<Handler, Error> {
         match pin {
             PwmPin::ISet => {
                 channels.channel_state(channel).pid_engaged = false;
@@ -206,8 +204,13 @@ impl Handler {
         Ok(Handler::Handled)
     }
 
-    fn set_center_point(socket: &mut TcpSocket, channels: &mut Channels, channel: usize, center: CenterPoint) -> Result<Handler, Error> {
-        let i_set = channels.get_i(channel);
+    fn set_center_point(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+        center: CenterPoint,
+    ) -> Result<Handler, Error> {
+        let i_set = channels.get_i_set(channel);
         let state = channels.channel_state(channel);
         state.center = center;
         if !state.pid_engaged {
@@ -217,65 +220,91 @@ impl Handler {
         Ok(Handler::Handled)
     }
 
-    fn set_pid (socket: &mut TcpSocket, channels: &mut Channels, channel: usize, parameter: PidParameter, value: f64) -> Result<Handler, Error> {
+    fn set_pid(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+        parameter: PidParameter,
+        value: f64,
+    ) -> Result<Handler, Error> {
         let pid = &mut channels.channel_state(channel).pid;
         use super::command_parser::PidParameter::*;
         match parameter {
-            Target =>
-                pid.target = value,
-            KP =>
-                pid.parameters.kp = value as f32,
-            KI => 
-                pid.update_ki(value as f32),
-            KD =>
-                pid.parameters.kd = value as f32,
-            OutputMin =>
-                pid.parameters.output_min = value as f32,
-            OutputMax =>
-                pid.parameters.output_max = value as f32,
+            Target => pid.target = value,
+            KP => pid.parameters.kp = value as f32,
+            KI => pid.update_ki(value as f32),
+            KD => pid.parameters.kd = value as f32,
+            OutputMin => pid.parameters.output_min = value as f32,
+            OutputMax => pid.parameters.output_max = value as f32,
         }
         send_line(socket, b"{}");
         Ok(Handler::Handled)
     }
 
-    fn set_steinhart_hart (socket: &mut TcpSocket, channels: &mut Channels, channel: usize, parameter: ShParameter, value: f64) -> Result<Handler, Error> {
+    fn set_steinhart_hart(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+        parameter: ShParameter,
+        value: f64,
+    ) -> Result<Handler, Error> {
         let sh = &mut channels.channel_state(channel).sh;
         use super::command_parser::ShParameter::*;
         match parameter {
             T0 => sh.t0 = ThermodynamicTemperature::new::<degree_celsius>(value),
-            B => sh.b = value,
+            B => sh.b = TemperatureInterval::new::<kelvin>(value),
             R0 => sh.r0 = ElectricalResistance::new::<ohm>(value),
         }
         send_line(socket, b"{}");
         Ok(Handler::Handled)
     }
 
-    fn reset_post_filter (socket: &mut TcpSocket, channels: &mut Channels, channel: usize) -> Result<Handler, Error> {
+    fn reset_post_filter(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+    ) -> Result<Handler, Error> {
         channels.adc.set_postfilter(channel as u8, None).unwrap();
         send_line(socket, b"{}");
         Ok(Handler::Handled)
     }
 
-    fn set_post_filter (socket: &mut TcpSocket, channels: &mut Channels, channel: usize, rate: f32) -> Result<Handler, Error> {
+    fn set_post_filter(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: usize,
+        rate: f32,
+    ) -> Result<Handler, Error> {
         let filter = ad7172::PostFilter::closest(rate);
         match filter {
             Some(filter) => {
-                channels.adc.set_postfilter(channel as u8, Some(filter)).unwrap();
+                channels
+                    .adc
+                    .set_postfilter(channel as u8, Some(filter))
+                    .unwrap();
                 send_line(socket, b"{}");
             }
             None => {
                 error!("unable to choose postfilter for rate {:.3}", rate);
-                send_line(socket, b"{{\"error\": \"unable to choose postfilter rate\"}}");
-                return Err(Error::PostFilterRateError);
+                send_line(
+                    socket,
+                    b"{{\"error\": \"unable to choose postfilter rate\"}}",
+                );
+                return Err(Error::PostFilterRate);
             }
         }
         Ok(Handler::Handled)
     }
 
-    fn load_channel (socket: &mut TcpSocket, channels: &mut Channels, store: &mut FlashStore, channel: Option<usize>) -> Result<Handler, Error> {
-        for c in 0..CHANNELS {
+    fn load_channel(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        store: &mut FlashStore,
+        channel: Option<usize>,
+    ) -> Result<Handler, Error> {
+        for (c, key) in CHANNEL_CONFIG_KEY.iter().enumerate().take(CHANNELS) {
             if channel.is_none() || channel == Some(c) {
-                match store.read_value::<ChannelConfig>(CHANNEL_CONFIG_KEY[c]) {
+                match store.read_value::<ChannelConfig>(key) {
                     Ok(Some(config)) => {
                         config.apply(channels, c);
                         send_line(socket, b"{}");
@@ -287,7 +316,7 @@ impl Handler {
                     Err(e) => {
                         error!("unable to load config from flash: {:?}", e);
                         let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                        return Err(Error::FlashError);
+                        return Err(Error::Flash);
                     }
                 }
             }
@@ -295,19 +324,24 @@ impl Handler {
         Ok(Handler::Handled)
     }
 
-    fn save_channel (socket: &mut TcpSocket, channels: &mut Channels, channel: Option<usize>, store: &mut FlashStore) -> Result<Handler, Error> {
-        for c in 0..CHANNELS {
+    fn save_channel(
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        channel: Option<usize>,
+        store: &mut FlashStore,
+    ) -> Result<Handler, Error> {
+        for (c, key) in CHANNEL_CONFIG_KEY.iter().enumerate().take(CHANNELS) {
             let mut store_value_buf = [0u8; 256];
             if channel.is_none() || channel == Some(c) {
                 let config = ChannelConfig::new(channels, c);
-                match store.write_value(CHANNEL_CONFIG_KEY[c], &config, &mut store_value_buf) {
+                match store.write_value(key, &config, &mut store_value_buf) {
                     Ok(()) => {
                         send_line(socket, b"{}");
                     }
                     Err(e) => {
                         error!("unable to save channel {} config to flash: {:?}", c, e);
                         let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                        return Err(Error::FlashError);
+                        return Err(Error::Flash);
                     }
                 }
             }
@@ -315,7 +349,11 @@ impl Handler {
         Ok(Handler::Handled)
     }
 
-    fn set_ipv4 (socket: &mut TcpSocket, store: &mut FlashStore, config: Ipv4Config) -> Result<Handler, Error> {
+    fn set_ipv4(
+        socket: &mut TcpSocket,
+        store: &mut FlashStore,
+        config: Ipv4Config,
+    ) -> Result<Handler, Error> {
         let _ = store
             .write_value("ipv4", &config, [0; 16])
             .map_err(|e| error!("unable to save ipv4 config to flash: {:?}", e));
@@ -324,7 +362,7 @@ impl Handler {
         Ok(Handler::NewIPV4(new_ipv4_config.unwrap()))
     }
 
-    fn reset (channels: &mut Channels) -> Result<Handler, Error> {
+    fn reset(channels: &mut Channels) -> Result<Handler, Error> {
         for i in 0..CHANNELS {
             channels.power_down(i);
         }
@@ -332,7 +370,7 @@ impl Handler {
         Ok(Handler::Reset)
     }
 
-    fn dfu (channels: &mut Channels) -> Result<Handler, Error> {
+    fn dfu(channels: &mut Channels) -> Result<Handler, Error> {
         for i in 0..CHANNELS {
             channels.power_down(i);
         }
@@ -343,9 +381,16 @@ impl Handler {
         Ok(Handler::Reset)
     }
 
-    fn set_fan(socket: &mut TcpSocket, fan_pwm: u32, fan_ctrl: &mut FanCtrl) -> Result<Handler, Error> {
+    fn set_fan(
+        socket: &mut TcpSocket,
+        fan_pwm: u32,
+        fan_ctrl: &mut FanCtrl,
+    ) -> Result<Handler, Error> {
         if !fan_ctrl.fan_available() {
-            send_line(socket, b"{ \"warning\": \"this thermostat doesn't have a fan!\" }");
+            send_line(
+                socket,
+                b"{ \"warning\": \"this thermostat doesn't have a fan!\" }",
+            );
             return Ok(Handler::Handled);
         }
         fan_ctrl.set_auto_mode(false);
@@ -367,14 +412,17 @@ impl Handler {
             Err(e) => {
                 error!("unable to serialize fan summary: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                Err(Error::ReportError)
+                Err(Error::Report)
             }
         }
     }
 
     fn fan_auto(socket: &mut TcpSocket, fan_ctrl: &mut FanCtrl) -> Result<Handler, Error> {
         if !fan_ctrl.fan_available() {
-            send_line(socket, b"{ \"warning\": \"this thermostat doesn't have a fan!\" }");
+            send_line(
+                socket,
+                b"{ \"warning\": \"this thermostat doesn't have a fan!\" }",
+            );
             return Ok(Handler::Handled);
         }
         fan_ctrl.set_auto_mode(true);
@@ -386,7 +434,13 @@ impl Handler {
         Ok(Handler::Handled)
     }
 
-    fn fan_curve(socket: &mut TcpSocket, fan_ctrl: &mut FanCtrl, k_a: f32, k_b: f32, k_c: f32) -> Result<Handler, Error> {
+    fn fan_curve(
+        socket: &mut TcpSocket,
+        fan_ctrl: &mut FanCtrl,
+        k_a: f32,
+        k_b: f32,
+        k_c: f32,
+    ) -> Result<Handler, Error> {
         fan_ctrl.set_curve(k_a, k_b, k_c);
         send_line(socket, b"{}");
         Ok(Handler::Handled)
@@ -407,40 +461,73 @@ impl Handler {
             Err(e) => {
                 error!("unable to serialize HWRev summary: {:?}", e);
                 let _ = writeln!(socket, "{{\"error\":\"{:?}\"}}", e);
-                Err(Error::ReportError)
+                Err(Error::Report)
             }
         }
     }
 
-    pub fn handle_command(command: Command, socket: &mut TcpSocket, channels: &mut Channels, session: &Session, store: &mut FlashStore, ipv4_config: &mut Ipv4Config, fan_ctrl: &mut FanCtrl, hwrev: HWRev) -> Result<Self, Error> {
+    pub fn handle_command(
+        command: Command,
+        socket: &mut TcpSocket,
+        channels: &mut Channels,
+        store: &mut FlashStore,
+        ipv4_config: &mut Ipv4Config,
+        fan_ctrl: &mut FanCtrl,
+        hwrev: HWRev,
+    ) -> Result<Self, Error> {
         match command {
             Command::Quit => Ok(Handler::CloseSocket),
-            Command::Reporting(_reporting) => Handler::reporting(socket),            
-            Command::Show(ShowCommand::Reporting) => Handler::show_report_mode(socket, session),            
             Command::Show(ShowCommand::Input) => Handler::show_report(socket, channels),
             Command::Show(ShowCommand::Pid) => Handler::show_pid(socket, channels),
-            Command::Show(ShowCommand::Pwm) => Handler::show_pwm(socket, channels),
-            Command::Show(ShowCommand::SteinhartHart) => Handler::show_steinhart_hart(socket, channels),
+            Command::Show(ShowCommand::Output) => Handler::show_pwm(socket, channels),
+            Command::Show(ShowCommand::SteinhartHart) => {
+                Handler::show_steinhart_hart(socket, channels)
+            }
             Command::Show(ShowCommand::PostFilter) => Handler::show_post_filter(socket, channels),
             Command::Show(ShowCommand::Ipv4) => Handler::show_ipv4(socket, ipv4_config),
-            Command::PwmPid { channel } => Handler::engage_pid(socket, channels, channel),
-            Command::Pwm { channel, pin, value } => Handler::set_pwm(socket, channels, channel, pin, value),
-            Command::CenterPoint { channel, center } => Handler::set_center_point(socket, channels, channel, center),
-            Command::Pid { channel, parameter, value } => Handler::set_pid(socket, channels, channel, parameter, value),
-            Command::SteinhartHart { channel, parameter, value } => Handler::set_steinhart_hart(socket, channels, channel, parameter, value),
-            Command::PostFilter { channel, rate: None } => Handler::reset_post_filter(socket, channels, channel),
-            Command::PostFilter { channel, rate: Some(rate) } => Handler::set_post_filter(socket, channels, channel, rate),
+            Command::OutputPid { channel } => Handler::engage_pid(socket, channels, channel),
+            Command::OutputPolarity { channel, polarity } => {
+                Handler::set_polarity(socket, channels, channel, polarity)
+            }
+            Command::Output {
+                channel,
+                pin,
+                value,
+            } => Handler::set_pwm(socket, channels, channel, pin, value),
+            Command::CenterPoint { channel, center } => {
+                Handler::set_center_point(socket, channels, channel, center)
+            }
+            Command::Pid {
+                channel,
+                parameter,
+                value,
+            } => Handler::set_pid(socket, channels, channel, parameter, value),
+            Command::SteinhartHart {
+                channel,
+                parameter,
+                value,
+            } => Handler::set_steinhart_hart(socket, channels, channel, parameter, value),
+            Command::PostFilter {
+                channel,
+                rate: None,
+            } => Handler::reset_post_filter(socket, channels, channel),
+            Command::PostFilter {
+                channel,
+                rate: Some(rate),
+            } => Handler::set_post_filter(socket, channels, channel, rate),
             Command::Load { channel } => Handler::load_channel(socket, channels, store, channel),
             Command::Save { channel } => Handler::save_channel(socket, channels, channel, store),
             Command::Ipv4(config) => Handler::set_ipv4(socket, store, config),
             Command::Reset => Handler::reset(channels),
             Command::Dfu => Handler::dfu(channels),
-            Command::FanSet {fan_pwm} => Handler::set_fan(socket, fan_pwm, fan_ctrl),
+            Command::FanSet { fan_pwm } => Handler::set_fan(socket, fan_pwm, fan_ctrl),
             Command::ShowFan => Handler::show_fan(socket, fan_ctrl),
             Command::FanAuto => Handler::fan_auto(socket, fan_ctrl),
-            Command::FanCurve { k_a, k_b, k_c } => Handler::fan_curve(socket, fan_ctrl, k_a, k_b, k_c),
+            Command::FanCurve { k_a, k_b, k_c } => {
+                Handler::fan_curve(socket, fan_ctrl, k_a, k_b, k_c)
+            }
             Command::FanCurveDefaults => Handler::fan_defaults(socket, fan_ctrl),
             Command::ShowHWRev => Handler::show_hwrev(socket, hwrev),
         }
     }
-}
+}

src/command_parser.rs

@@ -2,19 +2,20 @@ use core::fmt;
 use core::num::ParseIntError;
 use core::str::{from_utf8, Utf8Error};
 use nom::{
-    IResult,
     branch::alt,
     bytes::complete::{is_a, tag, take_while1},
-    character::{is_digit, complete::{char, one_of}},
+    character::{
+        complete::{char, one_of},
+        is_digit,
+    },
     combinator::{complete, map, opt, value},
-    sequence::preceded,
-    multi::{fold_many0, fold_many1},
     error::ErrorKind,
-    Needed,
+    multi::{fold_many0, fold_many1},
+    sequence::preceded,
+    IResult, Needed,
 };
 use num_traits::{Num, ParseFloatError};
-use serde::{Serialize, Deserialize};
-
+use serde::{Deserialize, Serialize};
 
 #[derive(Clone, Debug, PartialEq)]
 pub enum Error {
@@ -30,12 +31,9 @@ pub enum Error {
 impl<'t> From<nom::Err<(&'t [u8], ErrorKind)>> for Error {
     fn from(e: nom::Err<(&'t [u8], ErrorKind)>) -> Self {
         match e {
-            nom::Err::Incomplete(_) =>
-                Error::Incomplete,
-            nom::Err::Error((_, e)) =>
-                Error::Parser(e),
-            nom::Err::Failure((_, e)) =>
-                Error::Parser(e),
+            nom::Err::Incomplete(_) => Error::Incomplete,
+            nom::Err::Error((_, e)) => Error::Parser(e),
+            nom::Err::Failure((_, e)) => Error::Parser(e),
         }
     }
 }
@@ -61,8 +59,7 @@ impl From<ParseFloatError> for Error {
 impl fmt::Display for Error {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error> {
         match self {
-            Error::Incomplete =>
-                "incomplete input".fmt(fmt),
+            Error::Incomplete => "incomplete input".fmt(fmt),
             Error::UnexpectedInput(c) => {
                 "unexpected input: ".fmt(fmt)?;
                 c.fmt(fmt)
@@ -79,9 +76,7 @@ impl fmt::Display for Error {
                 "parsing int: ".fmt(fmt)?;
                 (e as &dyn core::fmt::Debug).fmt(fmt)
             }
-            Error::ParseFloat => {
-                "parsing float".fmt(fmt)
-            }
+            Error::ParseFloat => "parsing float".fmt(fmt),
         }
     }
 }
@@ -96,8 +91,7 @@ pub struct Ipv4Config {
 #[derive(Debug, Clone, PartialEq)]
 pub enum ShowCommand {
     Input,
-    Reporting,
-    Pwm,
+    Output,
     Pid,
     SteinhartHart,
     PostFilter,
@@ -132,10 +126,16 @@ pub enum PwmPin {
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
 pub enum CenterPoint {
-    Vref,
+    VRef,
     Override(f32),
 }
 
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub enum Polarity {
+    Normal,
+    Reversed,
+}
+
 #[derive(Debug, Clone, PartialEq)]
 pub enum Command {
     Quit,
@@ -148,17 +148,20 @@ pub enum Command {
     Reset,
     Ipv4(Ipv4Config),
     Show(ShowCommand),
-    Reporting(bool),
     /// PWM parameter setting
-    Pwm {
+    Output {
         channel: usize,
         pin: PwmPin,
         value: f64,
     },
     /// Enable PID control for `i_set`
-    PwmPid {
+    OutputPid {
         channel: usize,
     },
+    OutputPolarity {
+        channel: usize,
+        polarity: Polarity,
+    },
     CenterPoint {
         channel: usize,
         center: CenterPoint,
@@ -180,7 +183,7 @@ pub enum Command {
     },
     Dfu,
     FanSet {
-        fan_pwm: u32
+        fan_pwm: u32,
     },
     FanAuto,
     ShowFan,
@@ -194,12 +197,7 @@ pub enum Command {
 }
 
 fn end(input: &[u8]) -> IResult<&[u8], ()> {
-    complete(
-        fold_many0(
-            one_of("\r\n\t "),
-            (), |(), _| ()
-        )
-    )(input)
+    complete(fold_many0(one_of("\r\n\t "), (), |(), _| ()))(input)
 }
 
 fn whitespace(input: &[u8]) -> IResult<&[u8], ()> {
@@ -207,38 +205,25 @@ fn whitespace(input: &[u8]) -> IResult<&[u8], ()> {
 }
 
 fn unsigned(input: &[u8]) -> IResult<&[u8], Result<u32, Error>> {
-    take_while1(is_digit)(input)
-        .map(|(input, digits)| {
-            let result =
-                from_utf8(digits)
-                .map_err(|e| e.into())
-                .and_then(|digits| u32::from_str_radix(digits, 10)
-                     .map_err(|e| e.into())
-                );
-            (input, result)
-        })
+    take_while1(is_digit)(input).map(|(input, digits)| {
+        let result = from_utf8(digits)
+            .map_err(|e| e.into())
+            .and_then(|digits| digits.parse::<u32>().map_err(|e| e.into()));
+        (input, result)
+    })
 }
 
 fn float(input: &[u8]) -> IResult<&[u8], Result<f64, Error>> {
     let (input, sign) = opt(is_a("-"))(input)?;
     let negative = sign.is_some();
-    let (input, digits) = take_while1(|c| is_digit(c) || c == '.' as u8)(input)?;
-    let result =
-        from_utf8(digits)
+    let (input, digits) = take_while1(|c| is_digit(c) || c == b'.')(input)?;
+    let result = from_utf8(digits)
         .map_err(|e| e.into())
-        .and_then(|digits| f64::from_str_radix(digits, 10)
-                  .map_err(|e| e.into())
-        )
+        .and_then(|digits| f64::from_str_radix(digits, 10).map_err(|e| e.into()))
         .map(|result: f64| if negative { -result } else { result });
     Ok((input, result))
 }
 
-fn off_on(input: &[u8]) -> IResult<&[u8], bool> {
-    alt((value(false, tag("off")),
-         value(true, tag("on"))
-    ))(input)
-}
-
 fn channel(input: &[u8]) -> IResult<&[u8], usize> {
     map(one_of("01"), |c| (c as usize) - ('0' as usize))(input)
 }
@@ -246,83 +231,55 @@ fn channel(input: &[u8]) -> IResult<&[u8], usize> {
 fn report(input: &[u8]) -> IResult<&[u8], Command> {
     preceded(
         tag("report"),
-        alt((
-            preceded(
-                whitespace,
-                preceded(
-                    tag("mode"),
-                    alt((
-                        preceded(
-                            whitespace,
-                            // `report mode <on | off>` - Switch repoting mode
-                            map(off_on, Command::Reporting)
-                        ),
-                        // `report mode` - Show current reporting state
-                        value(Command::Show(ShowCommand::Reporting), end)
-                    ))
-                )),
-            // `report` - Report once
-            value(Command::Show(ShowCommand::Input), end)
-        ))
+        // `report` - Report once
+        value(Command::Show(ShowCommand::Input), end),
     )(input)
 }
 
 fn pwm_setup(input: &[u8]) -> IResult<&[u8], Result<(PwmPin, f64), Error>> {
-    let result_with_pin = |pin: PwmPin|
-        move |result: Result<f64, Error>|
-        result.map(|value| (pin, value));
+    let result_with_pin =
+        |pin: PwmPin| move |result: Result<f64, Error>| result.map(|value| (pin, value));
 
     alt((
         map(
-            preceded(
-                tag("i_set"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::ISet)
+            preceded(tag("i_set"), preceded(whitespace, float)),
+            result_with_pin(PwmPin::ISet),
         ),
         map(
-            preceded(
-                tag("max_i_pos"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::MaxIPos)
+            preceded(tag("max_i_pos"), preceded(whitespace, float)),
+            result_with_pin(PwmPin::MaxIPos),
         ),
         map(
-            preceded(
-                tag("max_i_neg"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::MaxINeg)
+            preceded(tag("max_i_neg"), preceded(whitespace, float)),
+            result_with_pin(PwmPin::MaxINeg),
         ),
         map(
-            preceded(
-                tag("max_v"),
-                preceded(
-                    whitespace,
-                    float
-                )
-            ),
-            result_with_pin(PwmPin::MaxV)
-        ))
-    )(input)
+            preceded(tag("max_v"), preceded(whitespace, float)),
+            result_with_pin(PwmPin::MaxV),
+        ),
+    ))(input)
 }
 
-/// `pwm <0-1> pid` - Set PWM to be controlled by PID
-fn pwm_pid(input: &[u8]) -> IResult<&[u8], ()> {
+/// `output <0-1> pid` - Set output to be controlled by PID
+fn output_pid(input: &[u8]) -> IResult<&[u8], ()> {
     value((), tag("pid"))(input)
 }
 
-fn pwm(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    let (input, _) = tag("pwm")(input)?;
+fn output_polarity(input: &[u8]) -> IResult<&[u8], Polarity> {
+    preceded(
+        tag("polarity"),
+        preceded(
+            whitespace,
+            alt((
+                value(Polarity::Normal, tag("normal")),
+                value(Polarity::Reversed, tag("reversed")),
+            )),
+        ),
+    )(input)
+}
+
+fn output(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
+    let (input, _) = tag("output")(input)?;
     alt((
         |input| {
             let (input, _) = whitespace(input)?;
@@ -330,23 +287,32 @@ fn pwm(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
             let (input, _) = whitespace(input)?;
             let (input, result) = alt((
                 |input| {
-                    let (input, ()) = pwm_pid(input)?;
-                    Ok((input, Ok(Command::PwmPid { channel })))
+                    let (input, ()) = output_pid(input)?;
+                    Ok((input, Ok(Command::OutputPid { channel })))
+                },
+                |input| {
+                    let (input, polarity) = output_polarity(input)?;
+                    Ok((input, Ok(Command::OutputPolarity { channel, polarity })))
                 },
                 |input| {
                     let (input, config) = pwm_setup(input)?;
                     match config {
-                        Ok((pin, value)) =>
-                            Ok((input, Ok(Command::Pwm { channel, pin, value }))),
-                        Err(e) =>
-                            Ok((input, Err(e))),
+                        Ok((pin, value)) => Ok((
+                            input,
+                            Ok(Command::Output {
+                                channel,
+                                pin,
+                                value,
+                            }),
+                        )),
+                        Err(e) => Ok((input, Err(e))),
                     }
                 },
             ))(input)?;
             end(input)?;
             Ok((input, result))
         },
-        value(Ok(Command::Show(ShowCommand::Pwm)), end)
+        value(Ok(Command::Show(ShowCommand::Output)), end),
     ))(input)
 }
 
@@ -355,36 +321,39 @@ fn center_point(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
     let (input, _) = whitespace(input)?;
     let (input, channel) = channel(input)?;
     let (input, _) = whitespace(input)?;
-    let (input, center) = alt((
-        value(Ok(CenterPoint::Vref), tag("vref")),
-        |input| {
-            let (input, value) = float(input)?;
-            Ok((input, value.map(|value| CenterPoint::Override(value as f32))))
-        }
-    ))(input)?;
+    let (input, center) = alt((value(Ok(CenterPoint::VRef), tag("vref")), |input| {
+        let (input, value) = float(input)?;
+        Ok((
+            input,
+            value.map(|value| CenterPoint::Override(value as f32)),
+        ))
+    }))(input)?;
     end(input)?;
-    Ok((input, center.map(|center| Command::CenterPoint {
-        channel,
-        center,
-    })))
+    Ok((
+        input,
+        center.map(|center| Command::CenterPoint { channel, center }),
+    ))
 }
 
 /// `pid <0-1> <parameter> <value>`
 fn pid_parameter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
     let (input, channel) = channel(input)?;
     let (input, _) = whitespace(input)?;
-    let (input, parameter) =
-        alt((value(PidParameter::Target, tag("target")),
-             value(PidParameter::KP, tag("kp")),
-             value(PidParameter::KI, tag("ki")),
-             value(PidParameter::KD, tag("kd")),
-             value(PidParameter::OutputMin, tag("output_min")),
-             value(PidParameter::OutputMax, tag("output_max")),
-        ))(input)?;
+    let (input, parameter) = alt((
+        value(PidParameter::Target, tag("target")),
+        value(PidParameter::KP, tag("kp")),
+        value(PidParameter::KI, tag("ki")),
+        value(PidParameter::KD, tag("kd")),
+        value(PidParameter::OutputMin, tag("output_min")),
+        value(PidParameter::OutputMax, tag("output_max")),
+    ))(input)?;
     let (input, _) = whitespace(input)?;
     let (input, value) = float(input)?;
-    let result = value
-        .map(|value| Command::Pid { channel, parameter, value });
+    let result = value.map(|value| Command::Pid {
+        channel,
+        parameter,
+        value,
+    });
     Ok((input, result))
 }
 
@@ -392,11 +361,8 @@ fn pid_parameter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
 fn pid(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
     let (input, _) = tag("pid")(input)?;
     alt((
-        preceded(
-            whitespace,
-            pid_parameter
-        ),
-        value(Ok(Command::Show(ShowCommand::Pid)), end)
+        preceded(whitespace, pid_parameter),
+        value(Ok(Command::Show(ShowCommand::Pid)), end),
     ))(input)
 }
 
@@ -404,15 +370,18 @@ fn pid(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
 fn steinhart_hart_parameter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
     let (input, channel) = channel(input)?;
     let (input, _) = whitespace(input)?;
-    let (input, parameter) =
-        alt((value(ShParameter::T0, tag("t0")),
-             value(ShParameter::B, tag("b")),
-             value(ShParameter::R0, tag("r0"))
-        ))(input)?;
+    let (input, parameter) = alt((
+        value(ShParameter::T0, tag("t0")),
+        value(ShParameter::B, tag("b")),
+        value(ShParameter::R0, tag("r0")),
+    ))(input)?;
     let (input, _) = whitespace(input)?;
     let (input, value) = float(input)?;
-    let result = value
-        .map(|value| Command::SteinhartHart { channel, parameter, value });
+    let result = value.map(|value| Command::SteinhartHart {
+        channel,
+        parameter,
+        value,
+    });
     Ok((input, result))
 }
 
@@ -420,42 +389,38 @@ fn steinhart_hart_parameter(input: &[u8]) -> IResult<&[u8], Result<Command, Erro
 fn steinhart_hart(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
     let (input, _) = tag("s-h")(input)?;
     alt((
-        preceded(
-            whitespace,
-            steinhart_hart_parameter
-        ),
-        value(Ok(Command::Show(ShowCommand::SteinhartHart)), end)
+        preceded(whitespace, steinhart_hart_parameter),
+        value(Ok(Command::Show(ShowCommand::SteinhartHart)), end),
     ))(input)
 }
 
 fn postfilter(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
     let (input, _) = tag("postfilter")(input)?;
     alt((
-        preceded(
-            whitespace,
-            |input| {
-                let (input, channel) = channel(input)?;
-                let (input, _) = whitespace(input)?;
-                alt((
-                    value(Ok(Command::PostFilter {
+        preceded(whitespace, |input| {
+            let (input, channel) = channel(input)?;
+            let (input, _) = whitespace(input)?;
+            alt((
+                value(
+                    Ok(Command::PostFilter {
                         channel,
                         rate: None,
-                    }), tag("off")),
-                    move |input| {
-                        let (input, _) = tag("rate")(input)?;
-                        let (input, _) = whitespace(input)?;
-                        let (input, rate) = float(input)?;
-                        let result = rate
-                            .map(|rate| Command::PostFilter {
-                                channel,
-                                rate: Some(rate as f32),
-                            });
-                        Ok((input, result))
-                    }
-                ))(input)
-            }
-        ),
-        value(Ok(Command::Show(ShowCommand::PostFilter)), end)
+                    }),
+                    tag("off"),
+                ),
+                move |input| {
+                    let (input, _) = tag("rate")(input)?;
+                    let (input, _) = whitespace(input)?;
+                    let (input, rate) = float(input)?;
+                    let result = rate.map(|rate| Command::PostFilter {
+                        channel,
+                        rate: Some(rate as f32),
+                    });
+                    Ok((input, result))
+                },
+            ))(input)
+        }),
+        value(Ok(Command::Show(ShowCommand::PostFilter)), end),
     ))(input)
 }
 
@@ -468,7 +433,7 @@ fn load(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
             let (input, _) = end(input)?;
             Ok((input, Some(channel)))
         },
-        value(None, end)
+        value(None, end),
     ))(input)?;
 
     let result = Ok(Command::Load { channel });
@@ -484,7 +449,7 @@ fn save(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
             let (input, _) = end(input)?;
             Ok((input, Some(channel)))
         },
-        value(None, end)
+        value(None, end),
     ))(input)?;
 
     let result = Ok(Command::Save { channel });
@@ -546,12 +511,17 @@ fn fan(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
                 },
                 |input| {
                     let (input, value) = unsigned(input)?;
-                    Ok((input, Ok(Command::FanSet { fan_pwm: value.unwrap_or(0)})))
+                    Ok((
+                        input,
+                        Ok(Command::FanSet {
+                            fan_pwm: value.unwrap_or(0),
+                        }),
+                    ))
                 },
             ))(input)?;
             Ok((input, result))
         },
-        value(Ok(Command::ShowFan), end)
+        value(Ok(Command::ShowFan), end),
     ))(input)
 }
 
@@ -571,8 +541,15 @@ fn fan_curve(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
                     let (input, k_b) = float(input)?;
                     let (input, _) = whitespace(input)?;
                     let (input, k_c) = float(input)?;
-                    if k_a.is_ok() && k_b.is_ok() && k_c.is_ok() {
-                        Ok((input, Ok(Command::FanCurve { k_a: k_a.unwrap() as f32, k_b: k_b.unwrap() as f32, k_c: k_c.unwrap() as f32 })))
+                    if let (Ok(k_a), Ok(k_b), Ok(k_c)) = (k_a, k_b, k_c) {
+                        Ok((
+                            input,
+                            Ok(Command::FanCurve {
+                                k_a: k_a as f32,
+                                k_b: k_b as f32,
+                                k_c: k_c as f32,
+                            }),
+                        ))
                     } else {
                         Err(nom::Err::Incomplete(Needed::Size(3)))
                     }
@@ -580,38 +557,36 @@ fn fan_curve(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
             ))(input)?;
             Ok((input, result))
         },
-        value(Err(Error::Incomplete), end)
+        value(Err(Error::Incomplete), end),
     ))(input)
 }
 
 fn command(input: &[u8]) -> IResult<&[u8], Result<Command, Error>> {
-    alt((value(Ok(Command::Quit), tag("quit")),
-         load,
-         save,
-         value(Ok(Command::Reset), tag("reset")),
-         ipv4,
-         map(report, Ok),
-         pwm,
-         center_point,
-         pid,
-         steinhart_hart,
-         postfilter,
-         value(Ok(Command::Dfu), tag("dfu")),
-         fan,
-         fan_curve,
-         value(Ok(Command::ShowHWRev), tag("hwrev")),
+    alt((
+        value(Ok(Command::Quit), tag("quit")),
+        load,
+        save,
+        value(Ok(Command::Reset), tag("reset")),
+        ipv4,
+        map(report, Ok),
+        output,
+        center_point,
+        pid,
+        steinhart_hart,
+        postfilter,
+        value(Ok(Command::Dfu), tag("dfu")),
+        fan,
+        fan_curve,
+        value(Ok(Command::ShowHWRev), tag("hwrev")),
     ))(input)
 }
 
 impl Command {
     pub fn parse(input: &[u8]) -> Result<Self, Error> {
         match command(input) {
-            Ok((input_remain, result)) if input_remain.len() == 0 =>
-                result,
-            Ok((input_remain, _)) =>
-                Err(Error::UnexpectedInput(input_remain[0])),
-            Err(e) =>
-                Err(e.into()),
+            Ok((input_remain, result)) if input_remain.is_empty() => result,
+            Ok((input_remain, _)) => Err(Error::UnexpectedInput(input_remain[0])),
+            Err(e) => Err(e.into()),
         }
     }
 }
@@ -659,21 +634,27 @@ mod test {
     #[test]
     fn parse_ipv4() {
         let command = Command::parse(b"ipv4 192.168.1.26/24");
-        assert_eq!(command, Ok(Command::Ipv4(Ipv4Config {
-            address: [192, 168, 1, 26],
-            mask_len: 24,
-            gateway: None,
-        })));
+        assert_eq!(
+            command,
+            Ok(Command::Ipv4(Ipv4Config {
+                address: [192, 168, 1, 26],
+                mask_len: 24,
+                gateway: None,
+            }))
+        );
     }
 
     #[test]
     fn parse_ipv4_and_gateway() {
         let command = Command::parse(b"ipv4 10.42.0.126/8 10.1.0.1");
-        assert_eq!(command, Ok(Command::Ipv4(Ipv4Config {
-            address: [10, 42, 0, 126],
-            mask_len: 8,
-            gateway: Some([10, 1, 0, 1]),
-        })));
+        assert_eq!(
+            command,
+            Ok(Command::Ipv4(Ipv4Config {
+                address: [10, 42, 0, 126],
+                mask_len: 8,
+                gateway: Some([10, 1, 0, 1]),
+            }))
+        );
     }
 
     #[test]
@@ -683,69 +664,73 @@ mod test {
     }
 
     #[test]
-    fn parse_report_mode() {
-        let command = Command::parse(b"report mode");
-        assert_eq!(command, Ok(Command::Show(ShowCommand::Reporting)));
+    fn parse_output_i_set() {
+        let command = Command::parse(b"output 1 i_set 16383");
+        assert_eq!(
+            command,
+            Ok(Command::Output {
+                channel: 1,
+                pin: PwmPin::ISet,
+                value: 16383.0,
+            })
+        );
     }
 
     #[test]
-    fn parse_report_mode_on() {
-        let command = Command::parse(b"report mode on");
-        assert_eq!(command, Ok(Command::Reporting(true)));
+    fn parse_output_polarity() {
+        let command = Command::parse(b"pwm 0 polarity reversed");
+        assert_eq!(
+            command,
+            Ok(Command::OutputPolarity {
+                channel: 0,
+                polarity: Polarity::Reversed,
+            })
+        );
     }
 
     #[test]
-    fn parse_report_mode_off() {
-        let command = Command::parse(b"report mode off");
-        assert_eq!(command, Ok(Command::Reporting(false)));
+    fn parse_output_pid() {
+        let command = Command::parse(b"output 0 pid");
+        assert_eq!(command, Ok(Command::OutputPid { channel: 0 }));
     }
 
     #[test]
-    fn parse_pwm_i_set() {
-        let command = Command::parse(b"pwm 1 i_set 16383");
-        assert_eq!(command, Ok(Command::Pwm {
-            channel: 1,
-            pin: PwmPin::ISet,
-            value: 16383.0,
-        }));
+    fn parse_output_max_i_pos() {
+        let command = Command::parse(b"output 0 max_i_pos 7");
+        assert_eq!(
+            command,
+            Ok(Command::Output {
+                channel: 0,
+                pin: PwmPin::MaxIPos,
+                value: 7.0,
+            })
+        );
     }
 
     #[test]
-    fn parse_pwm_pid() {
-        let command = Command::parse(b"pwm 0 pid");
-        assert_eq!(command, Ok(Command::PwmPid {
-            channel: 0,
-        }));
+    fn parse_output_max_i_neg() {
+        let command = Command::parse(b"output 0 max_i_neg 128");
+        assert_eq!(
+            command,
+            Ok(Command::Output {
+                channel: 0,
+                pin: PwmPin::MaxINeg,
+                value: 128.0,
+            })
+        );
     }
 
     #[test]
-    fn parse_pwm_max_i_pos() {
-        let command = Command::parse(b"pwm 0 max_i_pos 7");
-        assert_eq!(command, Ok(Command::Pwm {
-            channel: 0,
-            pin: PwmPin::MaxIPos,
-            value: 7.0,
-        }));
-    }
-
-    #[test]
-    fn parse_pwm_max_i_neg() {
-        let command = Command::parse(b"pwm 0 max_i_neg 128");
-        assert_eq!(command, Ok(Command::Pwm {
-            channel: 0,
-            pin: PwmPin::MaxINeg,
-            value: 128.0,
-        }));
-    }
-
-    #[test]
-    fn parse_pwm_max_v() {
-        let command = Command::parse(b"pwm 0 max_v 32768");
-        assert_eq!(command, Ok(Command::Pwm {
-            channel: 0,
-            pin: PwmPin::MaxV,
-            value: 32768.0,
-        }));
+    fn parse_output_max_v() {
+        let command = Command::parse(b"output 0 max_v 32768");
+        assert_eq!(
+            command,
+            Ok(Command::Output {
+                channel: 0,
+                pin: PwmPin::MaxV,
+                value: 32768.0,
+            })
+        );
     }
 
     #[test]
@@ -757,11 +742,14 @@ mod test {
     #[test]
     fn parse_pid_target() {
         let command = Command::parse(b"pid 0 target 36.5");
-        assert_eq!(command, Ok(Command::Pid {
-            channel: 0,
-            parameter: PidParameter::Target,
-            value: 36.5,
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::Pid {
+                channel: 0,
+                parameter: PidParameter::Target,
+                value: 36.5,
+            })
+        );
     }
 
     #[test]
@@ -773,11 +761,14 @@ mod test {
     #[test]
     fn parse_steinhart_hart_set() {
         let command = Command::parse(b"s-h 1 t0 23.05");
-        assert_eq!(command, Ok(Command::SteinhartHart {
-            channel: 1,
-            parameter: ShParameter::T0,
-            value: 23.05,
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::SteinhartHart {
+                channel: 1,
+                parameter: ShParameter::T0,
+                value: 23.05,
+            })
+        );
     }
 
     #[test]
@@ -789,37 +780,49 @@ mod test {
     #[test]
     fn parse_postfilter_off() {
         let command = Command::parse(b"postfilter 1 off");
-        assert_eq!(command, Ok(Command::PostFilter {
-            channel: 1,
-            rate: None,
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::PostFilter {
+                channel: 1,
+                rate: None,
+            })
+        );
     }
 
     #[test]
     fn parse_postfilter_rate() {
         let command = Command::parse(b"postfilter 0 rate 21");
-        assert_eq!(command, Ok(Command::PostFilter {
-            channel: 0,
-            rate: Some(21.0),
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::PostFilter {
+                channel: 0,
+                rate: Some(21.0),
+            })
+        );
     }
 
     #[test]
     fn parse_center_point() {
         let command = Command::parse(b"center 0 1.5");
-        assert_eq!(command, Ok(Command::CenterPoint {
-            channel: 0,
-            center: CenterPoint::Override(1.5),
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::CenterPoint {
+                channel: 0,
+                center: CenterPoint::Override(1.5),
+            })
+        );
     }
 
     #[test]
     fn parse_center_point_vref() {
         let command = Command::parse(b"center 1 vref");
-        assert_eq!(command, Ok(Command::CenterPoint {
-            channel: 1,
-            center: CenterPoint::Vref,
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::CenterPoint {
+                channel: 1,
+                center: CenterPoint::VRef,
+            })
+        );
     }
 
     #[test]
@@ -831,7 +834,7 @@ mod test {
     #[test]
     fn parse_fan_set() {
         let command = Command::parse(b"fan 42");
-        assert_eq!(command, Ok(Command::FanSet {fan_pwm: 42}));
+        assert_eq!(command, Ok(Command::FanSet { fan_pwm: 42 }));
     }
 
     #[test]
@@ -843,11 +846,14 @@ mod test {
     #[test]
     fn parse_fcurve_set() {
         let command = Command::parse(b"fcurve 1.2 3.4 5.6");
-        assert_eq!(command, Ok(Command::FanCurve {
-            k_a: 1.2,
-            k_b: 3.4,
-            k_c: 5.6
-        }));
+        assert_eq!(
+            command,
+            Ok(Command::FanCurve {
+                k_a: 1.2,
+                k_b: 3.4,
+                k_c: 5.6
+            })
+        );
     }
 
     #[test]

src/config.rs

@@ -1,17 +1,12 @@
-use num_traits::Zero;
-use serde::{Serialize, Deserialize};
-use uom::si::{
-    electric_potential::volt,
-    electric_current::ampere,
-    f64::{ElectricCurrent, ElectricPotential},
-};
 use crate::{
     ad7172::PostFilter,
     channels::Channels,
-    command_parser::CenterPoint,
-    pid,
-    steinhart_hart,
+    command_parser::{CenterPoint, Polarity},
+    pid, steinhart_hart,
 };
+use num_traits::Zero;
+use serde::{Deserialize, Serialize};
+use uom::si::f64::{ElectricCurrent, ElectricPotential};
 
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct ChannelConfig {
@@ -20,6 +15,7 @@ pub struct ChannelConfig {
     pid_target: f32,
     pid_engaged: bool,
     i_set: ElectricCurrent,
+    polarity: Polarity,
     sh: steinhart_hart::Parameters,
     pwm: PwmLimits,
     /// uses variant `PostFilter::Invalid` instead of `None` to save space
@@ -30,22 +26,25 @@ impl ChannelConfig {
     pub fn new(channels: &mut Channels, channel: usize) -> Self {
         let pwm = PwmLimits::new(channels, channel);
 
-        let adc_postfilter = channels.adc.get_postfilter(channel as u8)
+        let adc_postfilter = channels
+            .adc
+            .get_postfilter(channel as u8)
             .unwrap()
             .unwrap_or(PostFilter::Invalid);
 
         let state = channels.channel_state(channel);
-        let i_set = if state.pid_engaged { 
-            ElectricCurrent::zero() 
-        } else { 
-            state.i_set 
+        let i_set = if state.pid_engaged {
+            ElectricCurrent::zero()
+        } else {
+            state.i_set
         };
         ChannelConfig {
             center: state.center.clone(),
             pid: state.pid.parameters.clone(),
             pid_target: state.pid.target as f32,
             pid_engaged: state.pid_engaged,
-            i_set: i_set,
+            i_set,
+            polarity: state.polarity.clone(),
             sh: state.sh.clone(),
             pwm,
             adc_postfilter,
@@ -68,31 +67,32 @@ impl ChannelConfig {
         };
         let _ = channels.adc.set_postfilter(channel as u8, adc_postfilter);
         let _ = channels.set_i(channel, self.i_set);
+        channels.set_polarity(channel, self.polarity.clone());
     }
 }
 
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
-struct PwmLimits {
-    max_v: f64,
-    max_i_pos: f64,
-    max_i_neg: f64,
+pub struct PwmLimits {
+    pub max_v: ElectricPotential,
+    pub max_i_pos: ElectricCurrent,
+    pub max_i_neg: ElectricCurrent,
 }
 
 impl PwmLimits {
     pub fn new(channels: &mut Channels, channel: usize) -> Self {
-        let (max_v, _) = channels.get_max_v(channel);
-        let (max_i_pos, _) = channels.get_max_i_pos(channel);
-        let (max_i_neg, _) = channels.get_max_i_neg(channel);
+        let max_v = channels.get_max_v(channel);
+        let max_i_pos = channels.get_max_i_pos(channel);
+        let max_i_neg = channels.get_max_i_neg(channel);
         PwmLimits {
-            max_v: max_v.get::<volt>(),
-            max_i_pos: max_i_pos.get::<ampere>(),
-            max_i_neg: max_i_neg.get::<ampere>(),
+            max_v,
+            max_i_pos,
+            max_i_neg,
         }
     }
 
     pub fn apply(&self, channels: &mut Channels, channel: usize) {
-        channels.set_max_v(channel, ElectricPotential::new::<volt>(self.max_v));
-        channels.set_max_i_pos(channel, ElectricCurrent::new::<ampere>(self.max_i_pos));
-        channels.set_max_i_neg(channel, ElectricCurrent::new::<ampere>(self.max_i_neg));
+        channels.set_max_v(channel, self.max_v);
+        channels.set_max_i_pos(channel, self.max_i_pos);
+        channels.set_max_i_neg(channel, self.max_i_neg);
     }
 }

src/dfu.rs

@@ -14,7 +14,7 @@ pub unsafe fn set_dfu_trigger() {
 }
 
 /// Called by reset handler in lib.rs immediately after reset.
-/// This function should not be called outside of reset handler as 
+/// This function should not be called outside of reset handler as
 /// bootloader expects MCU to be in reset state when called.
 #[cfg(target_arch = "arm")]
 #[pre_init]
@@ -27,13 +27,13 @@ unsafe fn __pre_init() {
         rcc.apb2enr.modify(|_, w| w.syscfgen().set_bit());
 
         // Bypass BOOT pins and remap bootloader to 0x00000000
-        let syscfg = &*SYSCFG::ptr() ;
-        syscfg.memrm.write(|w| w.mem_mode().bits(0b01));  
+        let syscfg = &*SYSCFG::ptr();
+        syscfg.memrm.write(|w| w.mem_mode().bits(0b01));
 
         // Impose instruction and memory barriers
         cortex_m::asm::isb();
         cortex_m::asm::dsb();
-        
+
         asm!(
             // Set stack pointer to bootloader location
             "LDR R0, =0x1FFF0000",

src/fan_ctrl.rs

@@ -1,25 +1,17 @@
+use crate::{channels::MAX_TEC_I, command_handler::JsonBuffer, hw_rev::HWSettings};
 use num_traits::Float;
 use serde::Serialize;
 use stm32f4xx_hal::{
-    pwm::{self, PwmChannels},
     pac::TIM8,
+    pwm::{self, PwmChannels},
 };
-use uom::si::{
-    f64::ElectricCurrent,
-    electric_current::ampere,
-};
-use crate::{
-    hw_rev::HWSettings,
-    command_handler::JsonBuffer,
-    channels::MAX_TEC_I,
-};
+use uom::si::{electric_current::ampere, f64::ElectricCurrent};
 
 pub type FanPin = PwmChannels<TIM8, pwm::C4>;
 
 const MAX_USER_FAN_PWM: f32 = 100.0;
 const MIN_USER_FAN_PWM: f32 = 1.0;
 
-
 pub struct FanCtrl {
     fan: Option<FanPin>,
     fan_auto: bool,
@@ -56,7 +48,9 @@ impl FanCtrl {
         if self.fan_auto && self.hw_settings.fan_available {
             let scaled_current = self.abs_max_tec_i / MAX_TEC_I.get::<ampere>() as f32;
             // do not limit upper bound, as it will be limited in the set_pwm()
-            let pwm = (MAX_USER_FAN_PWM * (scaled_current * (scaled_current * self.k_a + self.k_b) + self.k_c)) as u32;
+            let pwm = (MAX_USER_FAN_PWM
+                * (scaled_current * (scaled_current * self.k_a + self.k_b) + self.k_c))
+                as u32;
             self.set_pwm(pwm);
         }
     }
@@ -89,18 +83,26 @@ impl FanCtrl {
     }
 
     pub fn restore_defaults(&mut self) {
-        self.set_curve(self.hw_settings.fan_k_a,
-                       self.hw_settings.fan_k_b,
-                       self.hw_settings.fan_k_c);
+        self.set_curve(
+            self.hw_settings.fan_k_a,
+            self.hw_settings.fan_k_b,
+            self.hw_settings.fan_k_c,
+        );
     }
 
     pub fn set_pwm(&mut self, fan_pwm: u32) -> f32 {
-        if self.fan.is_none() || (!self.pwm_enabled && !self.enable_pwm())  {
+        if self.fan.is_none() || (!self.pwm_enabled && !self.enable_pwm()) {
             return 0f32;
         }
         let fan = self.fan.as_mut().unwrap();
-        let fan_pwm = fan_pwm.min(MAX_USER_FAN_PWM as u32).max(MIN_USER_FAN_PWM as u32);
-        let duty = scale_number(fan_pwm as f32, self.hw_settings.min_fan_pwm, self.hw_settings.max_fan_pwm, MIN_USER_FAN_PWM, MAX_USER_FAN_PWM);
+        let fan_pwm = fan_pwm.clamp(MIN_USER_FAN_PWM as u32, MAX_USER_FAN_PWM as u32);
+        let duty = scale_number(
+            fan_pwm as f32,
+            self.hw_settings.min_fan_pwm,
+            self.hw_settings.max_fan_pwm,
+            MIN_USER_FAN_PWM,
+            MAX_USER_FAN_PWM,
+        );
         let max = fan.get_max_duty();
         let value = ((duty * (max as f32)) as u16).min(max);
         fan.set_duty(value);
@@ -119,8 +121,17 @@ impl FanCtrl {
         if let Some(fan) = &self.fan {
             let duty = fan.get_duty();
             let max = fan.get_max_duty();
-            scale_number(duty as f32 / (max as f32), MIN_USER_FAN_PWM, MAX_USER_FAN_PWM, self.hw_settings.min_fan_pwm, self.hw_settings.max_fan_pwm).round() as u32
-        } else { 0 }
+            scale_number(
+                duty as f32 / (max as f32),
+                MIN_USER_FAN_PWM,
+                MAX_USER_FAN_PWM,
+                self.hw_settings.min_fan_pwm,
+                self.hw_settings.max_fan_pwm,
+            )
+            .round() as u32
+        } else {
+            0
+        }
     }
 
     fn enable_pwm(&mut self) -> bool {
@@ -136,7 +147,6 @@ impl FanCtrl {
     }
 }
 
-
 fn scale_number(unscaled: f32, to_min: f32, to_max: f32, from_min: f32, from_max: f32) -> f32 {
     (to_max - to_min) * (unscaled - from_min) / (from_max - from_min) + to_min
 }

src/flash_store.rs

@@ -1,9 +1,9 @@
-use log::{info, error};
+use log::{error, info};
+use sfkv::{Store, StoreBackend};
 use stm32f4xx_hal::{
     flash::{Error, FlashExt},
     stm32::FLASH,
 };
-use sfkv::{Store, StoreBackend};
 
 /// 16 KiB
 pub const FLASH_SECTOR_SIZE: usize = 0x4000;
@@ -21,9 +21,7 @@ pub struct FlashBackend {
 }
 
 fn get_offset() -> usize {
-    unsafe {
-        (&_config_start as *const usize as usize) - (&_flash_start as *const usize as usize)
-    }    
+    unsafe { (&_config_start as *const usize as usize) - (&_flash_start as *const usize as usize) }
 }
 
 impl StoreBackend for FlashBackend {
@@ -40,7 +38,8 @@ impl StoreBackend for FlashBackend {
     }
 
     fn program(&mut self, offset: usize, payload: &[u8]) -> Result<(), Self::Error> {
-        self.flash.unlocked()
+        self.flash
+            .unlocked()
             .program(get_offset() + offset, payload.iter())
     }
 
@@ -60,7 +59,8 @@ pub fn store(flash: FLASH) -> FlashStore {
         Ok(_) => {}
         Err(e) => {
             error!("corrupt store, erasing. error: {:?}", e);
-            let _ = store.erase()
+            let _ = store
+                .erase()
                 .map_err(|e| error!("flash erase failed: {:?}", e));
         }
     }

src/hw_rev.rs

@@ -1,9 +1,6 @@
 use serde::Serialize;
 
-use crate::{
-    pins::HWRevPins,
-    command_handler::JsonBuffer,
-};
+use crate::{command_handler::JsonBuffer, pins::HWRevPins};
 
 #[derive(Serialize, Copy, Clone)]
 pub struct HWRev {
@@ -31,13 +28,17 @@ struct HWSummary<'a> {
 
 impl HWRev {
     pub fn detect_hw_rev(hwrev_pins: &HWRevPins) -> Self {
-        let (h0, h1, h2, h3) = (hwrev_pins.hwrev0.is_high(), hwrev_pins.hwrev1.is_high(),
-                                hwrev_pins.hwrev2.is_high(), hwrev_pins.hwrev3.is_high());
+        let (h0, h1, h2, h3) = (
+            hwrev_pins.hwrev0.is_high(),
+            hwrev_pins.hwrev1.is_high(),
+            hwrev_pins.hwrev2.is_high(),
+            hwrev_pins.hwrev3.is_high(),
+        );
         match (h0, h1, h2, h3) {
             (true, true, true, false) => HWRev { major: 1, minor: 0 },
             (true, false, false, false) => HWRev { major: 2, minor: 0 },
             (false, true, false, false) => HWRev { major: 2, minor: 2 },
-            (_, _, _, _) => HWRev { major: 0, minor: 0 }
+            (_, _, _, _) => HWRev { major: 0, minor: 0 },
         }
     }
 
@@ -70,13 +71,16 @@ impl HWRev {
                 fan_pwm_freq_hz: 0,
                 fan_available: false,
                 fan_pwm_recommended: false,
-            }
+            },
         }
     }
 
     pub fn summary(&self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
         let settings = self.settings();
-        let summary = HWSummary { rev: self, settings: &settings };
+        let summary = HWSummary {
+            rev: self,
+            settings: &settings,
+        };
         serde_json_core::to_vec(&summary)
     }
-}
+}

src/init_log.rs

@@ -10,17 +10,15 @@ pub fn init_log() {
 
 #[cfg(feature = "semihosting")]
 pub fn init_log() {
+    use cortex_m_log::log::{init, Logger};
+    use cortex_m_log::printer::semihosting::{hio::HStdout, InterruptOk};
     use log::LevelFilter;
-    use cortex_m_log::log::{Logger, init};
-    use cortex_m_log::printer::semihosting::{InterruptOk, hio::HStdout};
     static mut LOGGER: Option<Logger<InterruptOk<HStdout>>> = None;
     let logger = Logger {
         inner: InterruptOk::<_>::stdout().expect("semihosting stdout"),
         level: LevelFilter::Info,
     };
-    let logger = unsafe {
-        LOGGER.get_or_insert(logger)
-    };
+    let logger = unsafe { LOGGER.get_or_insert(logger) };
 
     init(logger).expect("set logger");
 }

src/leds.rs

@@ -1,6 +1,6 @@
 use stm32f4xx_hal::{
     gpio::{
-        gpiod::{PD9, PD10, PD11},
+        gpiod::{PD10, PD11, PD9},
         Output, PushPull,
     },
     hal::digital::v2::OutputPin,

src/main.rs

@@ -8,30 +8,26 @@ use panic_halt as _;
 #[cfg(all(feature = "semihosting", not(test)))]
 use panic_semihosting as _;
 
-use log::{error, info, warn};
 use cortex_m::asm::wfi;
 use cortex_m_rt::entry;
+use log::{error, info, warn};
+use smoltcp::{socket::TcpSocket, time::Instant, wire::EthernetAddress};
 use stm32f4xx_hal::{
-    hal::watchdog::{WatchdogEnable, Watchdog},
+    hal::watchdog::{Watchdog, WatchdogEnable},
     rcc::RccExt,
     stm32::{CorePeripherals, Peripherals, SCB},
-    time::{U32Ext, MegaHertz},
+    time::{MegaHertz, U32Ext},
     watchdog::IndependentWatchdog,
 };
-use smoltcp::{
-    time::Instant,
-    socket::TcpSocket,
-    wire::EthernetAddress,
-};
 
 mod init_log;
 use init_log::init_log;
-mod usb;
 mod leds;
 mod pins;
+mod usb;
 use pins::Pins;
-mod ad7172;
 mod ad5680;
+mod ad7172;
 mod net;
 mod server;
 use server::Server;
@@ -39,18 +35,18 @@ mod session;
 use session::{Session, SessionInput};
 mod command_parser;
 use command_parser::Ipv4Config;
-mod timer;
+mod channels;
 mod pid;
 mod steinhart_hart;
-mod channels;
-use channels::{CHANNELS, Channels};
+mod timer;
+use channels::{Channels, CHANNELS};
 mod channel;
 mod channel_state;
 mod config;
 use config::ChannelConfig;
-mod flash_store;
-mod dfu;
 mod command_handler;
+mod dfu;
+mod flash_store;
 use command_handler::Handler;
 mod fan_ctrl;
 use fan_ctrl::FanCtrl;
@@ -73,19 +69,19 @@ fn send_line(socket: &mut TcpSocket, data: &[u8]) -> bool {
         // instead of sending incomplete line
         warn!(
             "TCP socket has only {}/{} needed {}",
-            send_free + 1, socket.send_capacity(), data.len(),
+            send_free + 1,
+            socket.send_capacity(),
+            data.len(),
         );
     } else {
-        match socket.send_slice(&data) {
+        match socket.send_slice(data) {
             Ok(sent) if sent == data.len() => {
                 let _ = socket.send_slice(b"\n");
                 // success
-                return true
+                return true;
             }
-            Ok(sent) =>
-                warn!("sent only {}/{} bytes", sent, data.len()),
-            Err(e) =>
-                error!("error sending line: {:?}", e),
+            Ok(sent) => warn!("sent only {}/{} bytes", sent, data.len()),
+            Err(e) => error!("error sending line: {:?}", e),
         }
     }
     // not success
@@ -104,13 +100,15 @@ fn main() -> ! {
     cp.SCB.enable_dcache(&mut cp.CPUID);
 
     let dp = Peripherals::take().unwrap();
-    let clocks = dp.RCC.constrain()
+    let clocks = dp
+        .RCC
+        .constrain()
         .cfgr
         .use_hse(HSE)
         .sysclk(168.mhz())
         .hclk(168.mhz())
-        .pclk1(32.mhz())
-        .pclk2(64.mhz())
+        .pclk1(42.mhz())
+        .pclk2(84.mhz())
         .freeze();
 
     let mut wd = IndependentWatchdog::new(dp.IWDG);
@@ -120,14 +118,15 @@ fn main() -> ! {
     timer::setup(cp.SYST, clocks);
 
     let (pins, mut leds, mut eeprom, eth_pins, usb, fan, hwrev, hw_settings) = Pins::setup(
-        clocks, dp.TIM1, dp.TIM3, dp.TIM8,
-        dp.GPIOA, dp.GPIOB, dp.GPIOC, dp.GPIOD, dp.GPIOE, dp.GPIOF, dp.GPIOG,
+        clocks,
+        (dp.TIM1, dp.TIM3, dp.TIM8),
+        (
+            dp.GPIOA, dp.GPIOB, dp.GPIOC, dp.GPIOD, dp.GPIOE, dp.GPIOF, dp.GPIOG,
+        ),
         dp.I2C1,
-        dp.SPI2, dp.SPI4, dp.SPI5,
+        (dp.SPI2, dp.SPI4, dp.SPI5),
         dp.ADC1,
-        dp.OTG_FS_GLOBAL,
-        dp.OTG_FS_DEVICE,
-        dp.OTG_FS_PWRCLK,
+        (dp.OTG_FS_GLOBAL, dp.OTG_FS_DEVICE, dp.OTG_FS_PWRCLK),
     );
 
     leds.r1.on();
@@ -139,14 +138,11 @@ fn main() -> ! {
     let mut store = flash_store::store(dp.FLASH);
 
     let mut channels = Channels::new(pins);
-    for c in 0..CHANNELS {
-        match store.read_value::<ChannelConfig>(CHANNEL_CONFIG_KEY[c]) {
-            Ok(Some(config)) =>
-                config.apply(&mut channels, c),
-            Ok(None) =>
-                error!("flash config not found for channel {}", c),
-            Err(e) =>
-                error!("unable to load config {} from flash: {:?}", c, e),
+    for (c, key) in CHANNEL_CONFIG_KEY.iter().enumerate().take(CHANNELS) {
+        match store.read_value::<ChannelConfig>(key) {
+            Ok(Some(config)) => config.apply(&mut channels, c),
+            Ok(None) => error!("flash config not found for channel {}", c),
+            Err(e) => error!("unable to load config {} from flash: {:?}", c, e),
         }
     }
 
@@ -159,11 +155,9 @@ fn main() -> ! {
         gateway: None,
     };
     match store.read_value("ipv4") {
-        Ok(Some(config)) =>
-            ipv4_config = config,
+        Ok(Some(config)) => ipv4_config = config,
         Ok(None) => {}
-        Err(e) =>
-            error!("cannot read ipv4 config: {:?}", e),
+        Err(e) => error!("cannot read ipv4 config: {:?}", e),
     }
 
     // EEPROM ships with a read-only EUI-48 identifier
@@ -172,118 +166,115 @@ fn main() -> ! {
     let hwaddr = EthernetAddress(eui48);
     info!("EEPROM MAC address: {}", hwaddr);
 
-    net::run(clocks, dp.ETHERNET_MAC, dp.ETHERNET_DMA, eth_pins, hwaddr, ipv4_config.clone(), |iface| {
-        Server::<Session>::run(iface, |server| {
-            leds.r1.off();
-            let mut should_reset = false;
+    net::run(
+        clocks,
+        dp.ETHERNET_MAC,
+        dp.ETHERNET_DMA,
+        eth_pins,
+        hwaddr,
+        ipv4_config.clone(),
+        |iface| {
+            Server::<Session>::run(iface, |server| {
+                leds.r1.off();
+                let mut should_reset = false;
 
-            loop {
-                let mut new_ipv4_config = None;
-                let instant = Instant::from_millis(i64::from(timer::now()));
-                let updated_channel = channels.poll_adc(instant);
-                if let Some(channel) = updated_channel {
-                    server.for_each(|_, session| session.set_report_pending(channel.into()));
-                }
+                loop {
+                    let mut new_ipv4_config = None;
+                    let instant = Instant::from_millis(i64::from(timer::now()));
+                    channels.poll_adc(instant);
 
-                fan_ctrl.cycle(channels.current_abs_max_tec_i());
+                    fan_ctrl.cycle(channels.current_abs_max_tec_i());
 
-                if channels.pid_engaged() {
-                    leds.g3.on();
-                } else {
-                    leds.g3.off();
-                }
+                    if channels.pid_engaged() {
+                        leds.g3.on();
+                    } else {
+                        leds.g3.off();
+                    }
 
-                let instant = Instant::from_millis(i64::from(timer::now()));
-                cortex_m::interrupt::free(net::clear_pending);
-                server.poll(instant)
-                    .unwrap_or_else(|e| {
+                    let instant = Instant::from_millis(i64::from(timer::now()));
+                    cortex_m::interrupt::free(net::clear_pending);
+                    server.poll(instant).unwrap_or_else(|e| {
                         warn!("poll: {:?}", e);
                     });
 
-                if ! should_reset {
-                    // TCP protocol handling
-                    server.for_each(|mut socket, session| {
-                        if ! socket.is_active() {
-                            let _ = socket.listen(TCP_PORT);
-                            session.reset();
-                        } else if socket.may_send() && !socket.may_recv() {
-                            socket.close()
-                        } else if socket.can_send() && socket.can_recv() {
-                            match socket.recv(|buf| session.feed(buf)) {
-                                // SessionInput::Nothing happens when the line reader parses a string of characters that is not
-                                // followed by a newline character. Could be due to partial commands not terminated with newline,
-                                // socket RX ring buffer wraps around, or when the command is sent as seperate TCP packets etc.
-                                // Do nothing and feed more data to the line reader in the next loop cycle.
-                                Ok(SessionInput::Nothing) => {}
-                                Ok(SessionInput::Command(command)) => {
-                                    match Handler::handle_command(command, &mut socket, &mut channels, session, &mut store, &mut ipv4_config, &mut fan_ctrl, hwrev) {
-                                        Ok(Handler::NewIPV4(ip)) => new_ipv4_config = Some(ip),                                
-                                        Ok(Handler::Handled) => {},
-                                        Ok(Handler::CloseSocket) => socket.close(),
-                                        Ok(Handler::Reset) => should_reset = true,
-                                        Err(_) => {},
+                    if !should_reset {
+                        // TCP protocol handling
+                        server.for_each(|mut socket, session| {
+                            if !socket.is_active() {
+                                let _ = socket.listen(TCP_PORT);
+                                session.reset();
+                            } else if socket.may_send() && !socket.may_recv() {
+                                socket.close()
+                            } else if socket.can_send() && socket.can_recv() {
+                                match socket.recv(|buf| session.feed(buf)) {
+                                    // SessionInput::Nothing happens when the line reader parses a string of characters that is not
+                                    // followed by a newline character. Could be due to partial commands not terminated with newline,
+                                    // socket RX ring buffer wraps around, or when the command is sent as seperate TCP packets etc.
+                                    // Do nothing and feed more data to the line reader in the next loop cycle.
+                                    Ok(SessionInput::Nothing) => {}
+                                    Ok(SessionInput::Command(command)) => {
+                                        match Handler::handle_command(
+                                            command,
+                                            &mut socket,
+                                            &mut channels,
+                                            &mut store,
+                                            &mut ipv4_config,
+                                            &mut fan_ctrl,
+                                            hwrev,
+                                        ) {
+                                            Ok(Handler::NewIPV4(ip)) => new_ipv4_config = Some(ip),
+                                            Ok(Handler::Handled) => {}
+                                            Ok(Handler::CloseSocket) => socket.close(),
+                                            Ok(Handler::Reset) => should_reset = true,
+                                            Err(_) => {}
+                                        }
                                     }
-                                }
-                                Ok(SessionInput::Error(e)) => {
-                                    error!("session input: {:?}", e);
-                                    send_line(&mut socket, b"{ \"error\": \"invalid input\" }");
-                                }
-                                Err(_) =>
-                                    socket.close(),
-                            }
-                        } else if socket.can_send() {
-                            if let Some(channel) = session.is_report_pending() {
-                                match channels.reports_json() {
-                                    Ok(buf) => {
-                                        send_line(&mut socket, &buf[..]);
-                                        session.mark_report_sent(channel);
-                                    }
-                                    Err(e) => {
-                                        error!("unable to serialize report: {:?}", e);
-
+                                    Ok(SessionInput::Error(e)) => {
+                                        error!("session input: {:?}", e);
+                                        send_line(&mut socket, b"{ \"error\": \"invalid input\" }");
                                     }
+                                    Err(_) => socket.close(),
                                 }
                             }
+                        });
+                    } else {
+                        // Should reset, close all TCP sockets.
+                        let mut any_socket_alive = false;
+                        server.for_each(|mut socket, _| {
+                            if socket.is_active() {
+                                socket.abort();
+                                any_socket_alive = true;
+                            }
+                        });
+                        // Must let loop run for one more cycle to poll server for RST to be sent,
+                        // this makes sure system does not reset right after socket.abort() is called.
+                        if !any_socket_alive {
+                            SCB::sys_reset();
                         }
-                    });
-                } else {
-                    // Should reset, close all TCP sockets.
-                    let mut any_socket_alive = false;
-                    server.for_each(|mut socket, _| {                        
-                        if socket.is_active() {
-                            socket.abort();
-                            any_socket_alive = true;
-                        }
-                    });
-                    // Must let loop run for one more cycle to poll server for RST to be sent,
-                    // this makes sure system does not reset right after socket.abort() is called.
-                    if !any_socket_alive {
-                        SCB::sys_reset();
-                    }  
-                }
+                    }
 
-                // Apply new IPv4 address/gateway
-                new_ipv4_config.take()
-                    .map(|config| {
+                    // Apply new IPv4 address/gateway
+                    if let Some(config) = new_ipv4_config.take() {
                         server.set_ipv4_config(config.clone());
                         ipv4_config = config;
+                    };
+
+                    // Update watchdog
+                    wd.feed();
+
+                    leds.g4.off();
+                    cortex_m::interrupt::free(|cs| {
+                        if !net::is_pending(cs) {
+                            // Wait for interrupts
+                            // (Ethernet, SysTick, or USB)
+                            wfi();
+                        }
                     });
-
-                // Update watchdog
-                wd.feed();
-
-                leds.g4.off();
-                cortex_m::interrupt::free(|cs| {
-                    if !net::is_pending(cs) {
-                        // Wait for interrupts
-                        // (Ethernet, SysTick, or USB)
-                        wfi();
-                    }
-                });
-                leds.g4.on();
-            }
-        });
-    });
+                    leds.g4.on();
+                }
+            });
+        },
+    );
 
     unreachable!()
 }

src/net.rs

@@ -1,20 +1,17 @@
 //! As there is only one peripheral, supporting data structures are
 //! declared once and globally.
 
-use core::cell::RefCell;
-use cortex_m::interrupt::{CriticalSection, Mutex};
-use stm32f4xx_hal::{
-    rcc::Clocks,
-    pac::{interrupt, Peripherals, ETHERNET_MAC, ETHERNET_DMA},
-};
-use smoltcp::wire::{EthernetAddress, Ipv4Address, Ipv4Cidr};
-use smoltcp::iface::{
-    EthernetInterfaceBuilder, EthernetInterface,
-    NeighborCache, Routes,
-};
-use stm32_eth::{Eth, RingEntry, RxDescriptor, TxDescriptor};
 use crate::command_parser::Ipv4Config;
 use crate::pins::EthernetPins;
+use core::cell::RefCell;
+use cortex_m::interrupt::{CriticalSection, Mutex};
+use smoltcp::iface::{EthernetInterface, EthernetInterfaceBuilder, NeighborCache, Routes};
+use smoltcp::wire::{EthernetAddress, Ipv4Address, Ipv4Cidr};
+use stm32_eth::{Eth, RingEntry, RxDescriptor, TxDescriptor};
+use stm32f4xx_hal::{
+    pac::{interrupt, Peripherals, ETHERNET_DMA, ETHERNET_MAC},
+    rcc::Clocks,
+};
 
 /// Not on the stack so that stack can be placed in CCMRAM (which the
 /// ethernet peripheral cannot access)
@@ -30,27 +27,27 @@ static NET_PENDING: Mutex<RefCell<bool>> = Mutex::new(RefCell::new(false));
 /// Run callback `f` with ethernet driver and TCP/IP stack
 pub fn run<F>(
     clocks: Clocks,
-    ethernet_mac: ETHERNET_MAC, ethernet_dma: ETHERNET_DMA,
+    ethernet_mac: ETHERNET_MAC,
+    ethernet_dma: ETHERNET_DMA,
     eth_pins: EthernetPins,
     ethernet_addr: EthernetAddress,
     ipv4_config: Ipv4Config,
-    f: F
+    f: F,
 ) where
     F: FnOnce(EthernetInterface<&mut stm32_eth::Eth<'static, 'static>>),
 {
-    let rx_ring = unsafe {
-        RX_RING.get_or_insert(Default::default())
-    };
-    let tx_ring = unsafe {
-        TX_RING.get_or_insert(Default::default())
-    };
+    let rx_ring = unsafe { RX_RING.get_or_insert(Default::default()) };
+    let tx_ring = unsafe { TX_RING.get_or_insert(Default::default()) };
     // Ethernet driver
     let mut eth_dev = Eth::new(
-        ethernet_mac, ethernet_dma,
-        &mut rx_ring[..], &mut tx_ring[..],
+        ethernet_mac,
+        ethernet_dma,
+        &mut rx_ring[..],
+        &mut tx_ring[..],
         clocks,
         eth_pins,
-    ).unwrap();
+    )
+    .unwrap();
     eth_dev.enable_interrupt();
 
     // IP stack
@@ -76,8 +73,7 @@ pub fn run<F>(
 #[interrupt]
 fn ETH() {
     cortex_m::interrupt::free(|cs| {
-        *NET_PENDING.borrow(cs)
-            .borrow_mut() = true;
+        *NET_PENDING.borrow(cs).borrow_mut() = true;
     });
 
     let p = unsafe { Peripherals::steal() };
@@ -86,15 +82,13 @@ fn ETH() {
 
 /// Has an interrupt occurred since last call to `clear_pending()`?
 pub fn is_pending(cs: &CriticalSection) -> bool {
-    *NET_PENDING.borrow(cs)
-        .borrow()
+    *NET_PENDING.borrow(cs).borrow()
 }
 
 /// Clear the interrupt pending flag before polling the interface for
 /// data.
 pub fn clear_pending(cs: &CriticalSection) {
-    *NET_PENDING.borrow(cs)
-        .borrow_mut() = false;
+    *NET_PENDING.borrow(cs).borrow_mut() = false;
 }
 
 /// utility for destructuring into smoltcp types

src/pid.rs

@@ -1,4 +1,4 @@
-use serde::{Serialize, Deserialize};
+use serde::{Deserialize, Serialize};
 
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct Parameters {
@@ -29,38 +29,37 @@ impl Default for Parameters {
 #[derive(Clone)]
 pub struct Controller {
     pub parameters: Parameters,
-    pub target : f64,
-    u1 : f64,
-    x1 : f64,
-    x2 : f64,
-    pub y1 : f64,
+    pub target: f64,
+    u1: f64,
+    x1: f64,
+    x2: f64,
+    pub y1: f64,
 }
 
 impl Controller {
     pub const fn new(parameters: Parameters) -> Controller {
         Controller {
-            parameters: parameters,
-            target : 0.0,
-            u1 : 0.0,
-            x1 : 0.0,
-            x2 : 0.0,
-            y1 : 0.0,
+            parameters,
+            target: 0.0,
+            u1: 0.0,
+            x1: 0.0,
+            x2: 0.0,
+            y1: 0.0,
         }
     }
 
     // Based on https://hackmd.io/IACbwcOTSt6Adj3_F9bKuw PID implementation
     // Input x(t), target u(t), output y(t)
-    // y0' =   y1 - ki * u0   
+    // y0' =   y1 - ki * u0
     //       + x0 * (kp + ki + kd)
     //       - x1 * (kp + 2kd)
     //       + x2 * kd
     // y0  = clip(y0', ymin, ymax)
     pub fn update(&mut self, input: f64) -> f64 {
-        
         let mut output: f64 = self.y1 - self.target * f64::from(self.parameters.ki)
-                            + input * f64::from(self.parameters.kp + self.parameters.ki + self.parameters.kd)
-                            - self.x1 * f64::from(self.parameters.kp + 2.0 * self.parameters.kd)
-                            + self.x2 * f64::from(self.parameters.kd);
+            + input * f64::from(self.parameters.kp + self.parameters.ki + self.parameters.kd)
+            - self.x1 * f64::from(self.parameters.kp + 2.0 * self.parameters.kd)
+            + self.x2 * f64::from(self.parameters.kd);
         if output < self.parameters.output_min.into() {
             output = self.parameters.output_min.into();
         }
@@ -70,7 +69,7 @@ impl Controller {
         self.x2 = self.x1;
         self.x1 = input;
         self.u1 = self.target;
-        self.y1 = output;        
+        self.y1 = output;
         output
     }
 
@@ -109,17 +108,17 @@ mod test {
     #[test]
     fn test_controller() {
         // Initial and ambient temperature
-        const DEFAULT: f64 = 20.0;    
-        // Target temperature  
-        const TARGET: f64 = 40.0;   
-        // Control tolerance    
-        const ERROR: f64 = 0.01;    
-        // System response delay    
-        const DELAY: usize = 10;  
+        const DEFAULT: f64 = 20.0;
+        // Target temperature
+        const TARGET: f64 = 40.0;
+        // Control tolerance
+        const ERROR: f64 = 0.01;
+        // System response delay
+        const DELAY: usize = 10;
         // Heat lost
-        const LOSS: f64 = 0.05;    
-        // Limit simulation cycle, reaching this limit before settling fails test      
-        const CYCLE_LIMIT: u32 = 1000;  
+        const LOSS: f64 = 0.05;
+        // Limit simulation cycle, reaching this limit before settling fails test
+        const CYCLE_LIMIT: u32 = 1000;
 
         let mut pid = Controller::new(PARAMETERS.clone());
         pid.target = TARGET;

src/pins.rs

@@ -1,49 +1,41 @@
+use crate::{
+    channel::{Channel0, Channel1},
+    fan_ctrl::FanPin,
+    hw_rev::{HWRev, HWSettings},
+    leds::Leds,
+};
+use eeprom24x::{self, Eeprom24x};
+use stm32_eth::EthPins;
 use stm32f4xx_hal::{
     adc::Adc,
     gpio::{
-        AF5, Alternate, AlternateOD, Analog, Floating, Input,
-        gpioa::*,
-        gpiob::*,
-        gpioc::*,
-        gpioe::*,
-        gpiof::*,
-        gpiog::*,
-        GpioExt,
-        Output, PushPull,
+        gpioa::*, gpiob::*, gpioc::*, gpioe::*, gpiof::*, gpiog::*, Alternate, AlternateOD, Analog,
+        Floating, GpioExt, Input, Output, PushPull, AF5,
     },
     hal::{self, blocking::spi::Transfer, digital::v2::OutputPin},
     i2c::I2c,
     otg_fs::USB,
-    rcc::Clocks,
-    pwm::{self, PwmChannels},
-    spi::{Spi, NoMiso, TransferModeNormal},
     pac::{
-        ADC1,
-        GPIOA, GPIOB, GPIOC, GPIOD, GPIOE, GPIOF, GPIOG,
-        I2C1,
-        OTG_FS_GLOBAL, OTG_FS_DEVICE, OTG_FS_PWRCLK,
-        SPI2, SPI4, SPI5,
-        TIM1, TIM3, TIM8
+        ADC1, GPIOA, GPIOB, GPIOC, GPIOD, GPIOE, GPIOF, GPIOG, I2C1, OTG_FS_DEVICE, OTG_FS_GLOBAL,
+        OTG_FS_PWRCLK, SPI2, SPI4, SPI5, TIM1, TIM3, TIM8,
     },
-    timer::Timer,
+    pwm::{self, PwmChannels},
+    rcc::Clocks,
+    spi::{NoMiso, Spi, TransferModeNormal},
     time::U32Ext,
-};
-use eeprom24x::{self, Eeprom24x};
-use stm32_eth::EthPins;
-use crate::{
-    channel::{Channel0, Channel1},
-    leds::Leds,
-    fan_ctrl::FanPin,
-    hw_rev::{HWRev, HWSettings},
+    timer::Timer,
 };
 
 pub type Eeprom = Eeprom24x<
-    I2c<I2C1, (
-        PB8<AlternateOD<{ stm32f4xx_hal::gpio::AF4 }>>,
-        PB9<AlternateOD<{ stm32f4xx_hal::gpio::AF4 }>>
-    )>,
+    I2c<
+        I2C1,
+        (
+            PB8<AlternateOD<{ stm32f4xx_hal::gpio::AF4 }>>,
+            PB9<AlternateOD<{ stm32f4xx_hal::gpio::AF4 }>>,
+        ),
+    >,
     eeprom24x::page_size::B8,
-    eeprom24x::addr_size::OneByte
+    eeprom24x::addr_size::OneByte,
 >;
 
 pub type EthernetPins = EthPins<
@@ -54,14 +46,14 @@ pub type EthernetPins = EthPins<
     PB13<Input<Floating>>,
     PC4<Input<Floating>>,
     PC5<Input<Floating>>,
- >;
+>;
 
 pub trait ChannelPins {
     type DacSpi: Transfer<u8>;
     type DacSync: OutputPin;
     type Shdn: OutputPin;
     type VRefPin;
-    type ItecPin;
+    type ITecPin;
     type DacFeedbackPin;
     type TecUMeasPin;
 }
@@ -76,7 +68,7 @@ impl ChannelPins for Channel0 {
     type DacSync = PE4<Output<PushPull>>;
     type Shdn = PE10<Output<PushPull>>;
     type VRefPin = Channel0VRef;
-    type ItecPin = PA6<Analog>;
+    type ITecPin = PA6<Analog>;
     type DacFeedbackPin = PA4<Analog>;
     type TecUMeasPin = PC2<Analog>;
 }
@@ -91,13 +83,21 @@ impl ChannelPins for Channel1 {
     type DacSync = PF6<Output<PushPull>>;
     type Shdn = PE15<Output<PushPull>>;
     type VRefPin = Channel1VRef;
-    type ItecPin = PB0<Analog>;
+    type ITecPin = PB0<Analog>;
     type DacFeedbackPin = PA5<Analog>;
     type TecUMeasPin = PC3<Analog>;
 }
 
 /// SPI peripheral used for communication with the ADC
-pub type AdcSpi = Spi<SPI2, (PB10<Alternate<AF5>>, PB14<Alternate<AF5>>, PB15<Alternate<AF5>>), TransferModeNormal>;
+pub type AdcSpi = Spi<
+    SPI2,
+    (
+        PB10<Alternate<AF5>>,
+        PB14<Alternate<AF5>>,
+        PB15<Alternate<AF5>>,
+    ),
+    TransferModeNormal,
+>;
 pub type AdcNss = PB12<Output<PushPull>>;
 type Dac0Spi = Spi<SPI4, (PE2<Alternate<AF5>>, NoMiso, PE6<Alternate<AF5>>), TransferModeNormal>;
 type Dac1Spi = Spi<SPI5, (PF7<Alternate<AF5>>, NoMiso, PF9<Alternate<AF5>>), TransferModeNormal>;
@@ -108,7 +108,7 @@ pub struct ChannelPinSet<C: ChannelPins> {
     pub dac_sync: C::DacSync,
     pub shdn: C::Shdn,
     pub vref_pin: C::VRefPin,
-    pub itec_pin: C::ItecPin,
+    pub itec_pin: C::ITecPin,
     pub dac_feedback_pin: C::DacFeedbackPin,
     pub tec_u_meas_pin: C::TecUMeasPin,
 }
@@ -133,13 +133,34 @@ impl Pins {
     /// Setup GPIO pins and configure MCU peripherals
     pub fn setup(
         clocks: Clocks,
-        tim1: TIM1, tim3: TIM3, tim8: TIM8,
-        gpioa: GPIOA, gpiob: GPIOB, gpioc: GPIOC, gpiod: GPIOD, gpioe: GPIOE, gpiof: GPIOF, gpiog: GPIOG,
+        (tim1, tim3, tim8): (TIM1, TIM3, TIM8),
+        (gpioa, gpiob, gpioc, gpiod, gpioe, gpiof, gpiog): (
+            GPIOA,
+            GPIOB,
+            GPIOC,
+            GPIOD,
+            GPIOE,
+            GPIOF,
+            GPIOG,
+        ),
         i2c1: I2C1,
-        spi2: SPI2, spi4: SPI4, spi5: SPI5,
+        (spi2, spi4, spi5): (SPI2, SPI4, SPI5),
         adc1: ADC1,
-        otg_fs_global: OTG_FS_GLOBAL, otg_fs_device: OTG_FS_DEVICE, otg_fs_pwrclk: OTG_FS_PWRCLK,
-    ) -> (Self, Leds, Eeprom, EthernetPins, USB, Option<FanPin>, HWRev, HWSettings) {
+        (otg_fs_global, otg_fs_device, otg_fs_pwrclk): (
+            OTG_FS_GLOBAL,
+            OTG_FS_DEVICE,
+            OTG_FS_PWRCLK,
+        ),
+    ) -> (
+        Self,
+        Leds,
+        Eeprom,
+        EthernetPins,
+        USB,
+        Option<FanPin>,
+        HWRev,
+        HWSettings,
+    ) {
         let gpioa = gpioa.split();
         let gpiob = gpiob.split();
         let gpioc = gpioc.split();
@@ -154,23 +175,29 @@ impl Pins {
         let pins_adc = Adc::adc1(adc1, true, Default::default());
 
         let pwm = PwmPins::setup(
-            clocks, tim1, tim3,
-            gpioc.pc6, gpioc.pc7,
-            gpioe.pe9, gpioe.pe11,
-            gpioe.pe13, gpioe.pe14
+            clocks,
+            (tim1, tim3),
+            (gpioc.pc6, gpioc.pc7),
+            (gpioe.pe9, gpioe.pe11),
+            (gpioe.pe13, gpioe.pe14),
         );
 
-        let hwrev = HWRev::detect_hw_rev(&HWRevPins {hwrev0: gpiod.pd0, hwrev1: gpiod.pd1,
-            hwrev2: gpiod.pd2, hwrev3: gpiod.pd3});
+        let hwrev = HWRev::detect_hw_rev(&HWRevPins {
+            hwrev0: gpiod.pd0,
+            hwrev1: gpiod.pd1,
+            hwrev2: gpiod.pd2,
+            hwrev3: gpiod.pd3,
+        });
         let hw_settings = hwrev.settings();
 
-        let (dac0_spi, dac0_sync) = Self::setup_dac0(
-            clocks, spi4,
-            gpioe.pe2, gpioe.pe4, gpioe.pe6
-        );
+        let (dac0_spi, dac0_sync) = Self::setup_dac0(clocks, spi4, gpioe.pe2, gpioe.pe4, gpioe.pe6);
         let mut shdn0 = gpioe.pe10.into_push_pull_output();
-        let _ = shdn0.set_low();
-        let vref0_pin = if hwrev.major > 2 {Channel0VRef::Analog(gpioa.pa0.into_analog())} else {Channel0VRef::Disabled(gpioa.pa0)};
+        shdn0.set_low();
+        let vref0_pin = if hwrev.major > 2 {
+            Channel0VRef::Analog(gpioa.pa0.into_analog())
+        } else {
+            Channel0VRef::Disabled(gpioa.pa0)
+        };
         let itec0_pin = gpioa.pa6.into_analog();
         let dac_feedback0_pin = gpioa.pa4.into_analog();
         let tec_u_meas0_pin = gpioc.pc2.into_analog();
@@ -184,13 +211,14 @@ impl Pins {
             tec_u_meas_pin: tec_u_meas0_pin,
         };
 
-        let (dac1_spi, dac1_sync) = Self::setup_dac1(
-            clocks, spi5,
-            gpiof.pf7, gpiof.pf6, gpiof.pf9
-        );
+        let (dac1_spi, dac1_sync) = Self::setup_dac1(clocks, spi5, gpiof.pf7, gpiof.pf6, gpiof.pf9);
         let mut shdn1 = gpioe.pe15.into_push_pull_output();
-        let _ = shdn1.set_low();
-        let vref1_pin = if hwrev.major > 2 {Channel1VRef::Analog(gpioa.pa3.into_analog())} else {Channel1VRef::Disabled(gpioa.pa3)};
+        shdn1.set_low();
+        let vref1_pin = if hwrev.major > 2 {
+            Channel1VRef::Analog(gpioa.pa3.into_analog())
+        } else {
+            Channel1VRef::Disabled(gpioa.pa3)
+        };
         let itec1_pin = gpiob.pb0.into_analog();
         let dac_feedback1_pin = gpioa.pa5.into_analog();
         let tec_u_meas1_pin = gpioc.pc3.into_analog();
@@ -205,14 +233,19 @@ impl Pins {
         };
 
         let pins = Pins {
-            adc_spi, adc_nss,
+            adc_spi,
+            adc_nss,
             pins_adc,
             pwm,
             channel0,
             channel1,
         };
 
-        let leds = Leds::new(gpiod.pd9, gpiod.pd10.into_push_pull_output(), gpiod.pd11.into_push_pull_output());
+        let leds = Leds::new(
+            gpiod.pd9,
+            gpiod.pd10.into_push_pull_output(),
+            gpiod.pd11.into_push_pull_output(),
+        );
 
         let eeprom_scl = gpiob.pb8.into_alternate().set_open_drain();
         let eeprom_sda = gpiob.pb9.into_alternate().set_open_drain();
@@ -239,8 +272,13 @@ impl Pins {
         };
 
         let fan = if hw_settings.fan_available {
-             Some(Timer::new(tim8, &clocks).pwm(gpioc.pc9.into_alternate(), hw_settings.fan_pwm_freq_hz.hz()))
-        } else { None };
+            Some(
+                Timer::new(tim8, &clocks)
+                    .pwm(gpioc.pc9.into_alternate(), hw_settings.fan_pwm_freq_hz.hz()),
+            )
+        } else {
+            None
+        };
 
         (pins, leds, eeprom, eth_pins, usb, fan, hwrev, hw_settings)
     }
@@ -252,8 +290,7 @@ impl Pins {
         sck: PB10<M1>,
         miso: PB14<M2>,
         mosi: PB15<M3>,
-    ) -> AdcSpi
-    {
+    ) -> AdcSpi {
         let sck = sck.into_alternate();
         let miso = miso.into_alternate();
         let mosi = mosi.into_alternate();
@@ -262,13 +299,16 @@ impl Pins {
             (sck, miso, mosi),
             crate::ad7172::SPI_MODE,
             crate::ad7172::SPI_CLOCK,
-            clocks
+            clocks,
         )
     }
 
     fn setup_dac0<M1, M2, M3>(
-        clocks: Clocks, spi4: SPI4,
-        sclk: PE2<M1>, sync: PE4<M2>, sdin: PE6<M3>
+        clocks: Clocks,
+        spi4: SPI4,
+        sclk: PE2<M1>,
+        sync: PE4<M2>,
+        sdin: PE6<M3>,
     ) -> (Dac0Spi, <Channel0 as ChannelPins>::DacSync) {
         let sclk = sclk.into_alternate();
         let sdin = sdin.into_alternate();
@@ -277,7 +317,7 @@ impl Pins {
             (sclk, NoMiso {}, sdin),
             crate::ad5680::SPI_MODE,
             crate::ad5680::SPI_CLOCK,
-            clocks
+            clocks,
         );
         let sync = sync.into_push_pull_output();
 
@@ -285,8 +325,11 @@ impl Pins {
     }
 
     fn setup_dac1<M1, M2, M3>(
-        clocks: Clocks, spi5: SPI5,
-        sclk: PF7<M1>, sync: PF6<M2>, sdin: PF9<M3>
+        clocks: Clocks,
+        spi5: SPI5,
+        sclk: PF7<M1>,
+        sync: PF6<M2>,
+        sdin: PF9<M3>,
     ) -> (Dac1Spi, <Channel1 as ChannelPins>::DacSync) {
         let sclk = sclk.into_alternate();
         let sdin = sdin.into_alternate();
@@ -295,7 +338,7 @@ impl Pins {
             (sclk, NoMiso {}, sdin),
             crate::ad5680::SPI_MODE,
             crate::ad5680::SPI_CLOCK,
-            clocks
+            clocks,
         );
         let sync = sync.into_push_pull_output();
 
@@ -315,25 +358,18 @@ pub struct PwmPins {
 impl PwmPins {
     fn setup<M1, M2, M3, M4, M5, M6>(
         clocks: Clocks,
-        tim1: TIM1,
-        tim3: TIM3,
-        max_v0: PC6<M1>,
-        max_v1: PC7<M2>,
-        max_i_pos0: PE9<M3>,
-        max_i_pos1: PE11<M4>,
-        max_i_neg0: PE13<M5>,
-        max_i_neg1: PE14<M6>,
+        (tim1, tim3): (TIM1, TIM3),
+        (max_v0, max_v1): (PC6<M1>, PC7<M2>),
+        (max_i_pos0, max_i_pos1): (PE9<M3>, PE11<M4>),
+        (max_i_neg0, max_i_neg1): (PE13<M5>, PE14<M6>),
     ) -> PwmPins {
         let freq = 20u32.khz();
 
-        fn init_pwm_pin<P: hal::PwmPin<Duty=u16>>(pin: &mut P) {
+        fn init_pwm_pin<P: hal::PwmPin<Duty = u16>>(pin: &mut P) {
             pin.set_duty(0);
             pin.enable();
         }
-        let channels = (
-            max_v0.into_alternate(),
-            max_v1.into_alternate(),
-        );
+        let channels = (max_v0.into_alternate(), max_v1.into_alternate());
         //let (mut max_v0, mut max_v1) = pwm::tim3(tim3, channels, clocks, freq);
         let (mut max_v0, mut max_v1) = Timer::new(tim3, &clocks).pwm(channels, freq);
         init_pwm_pin(&mut max_v0);
@@ -353,9 +389,12 @@ impl PwmPins {
         init_pwm_pin(&mut max_i_neg1);
 
         PwmPins {
-            max_v0, max_v1,
-            max_i_pos0, max_i_pos1,
-            max_i_neg0, max_i_neg1,
+            max_v0,
+            max_v1,
+            max_i_pos0,
+            max_i_pos1,
+            max_i_neg0,
+            max_i_neg1,
         }
     }
 }

src/server.rs

@@ -1,25 +1,29 @@
+use crate::command_parser::Ipv4Config;
+use crate::net::split_ipv4_config;
 use smoltcp::{
     iface::EthernetInterface,
-    socket::{SocketSet, SocketHandle, TcpSocket, TcpSocketBuffer, SocketRef},
+    socket::{SocketHandle, SocketRef, SocketSet, TcpSocket, TcpSocketBuffer},
     time::Instant,
     wire::{IpAddress, IpCidr, Ipv4Address, Ipv4Cidr},
 };
-use crate::command_parser::Ipv4Config;
-use crate::net::split_ipv4_config;
 
 pub struct SocketState<S> {
     handle: SocketHandle,
     state: S,
 }
 
-impl<'a, S: Default> SocketState<S>{
-    fn new(sockets: &mut SocketSet<'a>, tcp_rx_storage: &'a mut [u8; TCP_RX_BUFFER_SIZE], tcp_tx_storage: &'a mut [u8; TCP_TX_BUFFER_SIZE]) -> SocketState<S> {
+impl<'a, S: Default> SocketState<S> {
+    fn new(
+        sockets: &mut SocketSet<'a>,
+        tcp_rx_storage: &'a mut [u8; TCP_RX_BUFFER_SIZE],
+        tcp_tx_storage: &'a mut [u8; TCP_TX_BUFFER_SIZE],
+    ) -> SocketState<S> {
         let tcp_rx_buffer = TcpSocketBuffer::new(&mut tcp_rx_storage[..]);
         let tcp_tx_buffer = TcpSocketBuffer::new(&mut tcp_tx_storage[..]);
         let tcp_socket = TcpSocket::new(tcp_rx_buffer, tcp_tx_buffer);
         SocketState::<S> {
             handle: sockets.add(tcp_socket),
-            state: S::default()
+            state: S::default(),
         }
     }
 }
@@ -50,7 +54,7 @@ impl<'a, 'b, S: Default> Server<'a, 'b, S> {
             ($rx_storage:ident, $tx_storage:ident) => {
                 let mut $rx_storage = [0; TCP_RX_BUFFER_SIZE];
                 let mut $tx_storage = [0; TCP_TX_BUFFER_SIZE];
-            }
+            };
         }
 
         create_rtx_storage!(tcp_rx_storage0, tcp_tx_storage0);
@@ -99,15 +103,10 @@ impl<'a, 'b, S: Default> Server<'a, 'b, S> {
     fn set_ipv4_address(&mut self, ipv4_address: Ipv4Cidr) {
         self.net.update_ip_addrs(|addrs| {
             for addr in addrs.iter_mut() {
-                match addr {
-                    IpCidr::Ipv4(_) => {
-                        *addr = IpCidr::Ipv4(ipv4_address);
-                        // done
-                        break
-                    }
-                    _ => {
-                        // skip
-                    }
+                if let IpCidr::Ipv4(_) = addr {
+                    *addr = IpCidr::Ipv4(ipv4_address);
+                    // done
+                    break;
                 }
             }
         });
@@ -116,10 +115,9 @@ impl<'a, 'b, S: Default> Server<'a, 'b, S> {
     fn set_gateway(&mut self, gateway: Option<Ipv4Address>) {
         let routes = self.net.routes_mut();
         match gateway {
-            None =>
-                routes.update(|routes_storage| {
-                    routes_storage.remove(&IpCidr::new(IpAddress::v4(0, 0, 0, 0), 0));
-                }),
+            None => routes.update(|routes_storage| {
+                routes_storage.remove(&IpCidr::new(IpAddress::v4(0, 0, 0, 0), 0));
+            }),
             Some(gateway) => {
                 routes.add_default_ipv4_route(gateway).unwrap();
             }

src/session.rs

@@ -1,5 +1,4 @@
 use super::command_parser::{Command, Error as ParserError};
-use super::channels::CHANNELS;
 
 const MAX_LINE_LEN: usize = 64;
 
@@ -46,15 +45,14 @@ pub enum SessionInput {
 
 impl From<Result<Command, ParserError>> for SessionInput {
     fn from(input: Result<Command, ParserError>) -> Self {
-        input.map(SessionInput::Command)
+        input
+            .map(SessionInput::Command)
             .unwrap_or_else(SessionInput::Error)
     }
 }
 
 pub struct Session {
     reader: LineReader,
-    reporting: bool,
-    report_pending: [bool; CHANNELS],
 }
 
 impl Default for Session {
@@ -67,43 +65,11 @@ impl Session {
     pub fn new() -> Self {
         Session {
             reader: LineReader::new(),
-            reporting: false,
-            report_pending: [false; CHANNELS],
         }
     }
 
     pub fn reset(&mut self) {
         self.reader = LineReader::new();
-        self.reporting = false;
-        self.report_pending = [false; CHANNELS];
-    }
-
-    pub fn reporting(&self) -> bool {
-        self.reporting
-    }
-
-    pub fn set_report_pending(&mut self, channel: usize) {
-        if self.reporting {
-            self.report_pending[channel] = true;
-        }
-    }
-
-    pub fn is_report_pending(&self) -> Option<usize> {
-        if ! self.reporting {
-            None
-        } else {
-            self.report_pending.iter()
-                .enumerate()
-                .fold(None, |result, (channel, report_pending)| {
-                    result.or_else(|| {
-                        if *report_pending { Some(channel) } else { None }
-                    })
-                })
-        }
-    }
-
-    pub fn mark_report_sent(&mut self, channel: usize) {
-        self.report_pending[channel] = false;
     }
 
     pub fn feed(&mut self, buf: &[u8]) -> (usize, SessionInput) {
@@ -111,18 +77,9 @@ impl Session {
         for (i, b) in buf.iter().enumerate() {
             buf_bytes = i + 1;
             let line = self.reader.feed(*b);
-            match line {
-                Some(line) => {
-                    let command = Command::parse(&line);
-                    match command {
-                        Ok(Command::Reporting(reporting)) => {
-                            self.reporting = reporting;
-                        }
-                        _ => {}
-                    }
-                    return (buf_bytes, command.into());
-                }
-                None => {}
+            if let Some(line) = line {
+                let command = Command::parse(line);
+                return (buf_bytes, command.into());
             }
         }
         (buf_bytes, SessionInput::Nothing)

src/steinhart_hart.rs

@@ -1,31 +1,29 @@
 use num_traits::float::Float;
+use serde::{Deserialize, Serialize};
 use uom::si::{
-    f64::{
-        ElectricalResistance,
-        ThermodynamicTemperature,
-    },
     electrical_resistance::ohm,
+    f64::{ElectricalResistance, TemperatureInterval, ThermodynamicTemperature},
     ratio::ratio,
+    temperature_interval::kelvin as kelvin_interval,
     thermodynamic_temperature::{degree_celsius, kelvin},
 };
-use serde::{Deserialize, Serialize};
 
 /// Steinhart-Hart equation parameters
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub struct Parameters {
     /// Base temperature
     pub t0: ThermodynamicTemperature,
-    /// Base resistance
+    /// Resistance at base temperature
     pub r0: ElectricalResistance,
     /// Beta
-    pub b: f64,
+    pub b: TemperatureInterval,
 }
 
 impl Parameters {
-    /// Perform the voltage to temperature conversion.
+    /// Perform the resistance to temperature conversion.
     pub fn get_temperature(&self, r: ElectricalResistance) -> ThermodynamicTemperature {
-        let inv_temp = 1.0 / self.t0.get::<kelvin>() + (r / self.r0).get::<ratio>().ln() / self.b;
-        ThermodynamicTemperature::new::<kelvin>(1.0 / inv_temp)
+        let temp = (self.t0.recip() + (r / self.r0).get::<ratio>().ln() / self.b).recip();
+        ThermodynamicTemperature::new::<kelvin>(temp.get::<kelvin_interval>())
     }
 }
 
@@ -34,7 +32,7 @@ impl Default for Parameters {
         Parameters {
             t0: ThermodynamicTemperature::new::<degree_celsius>(25.0),
             r0: ElectricalResistance::new::<ohm>(10_000.0),
-            b: 3800.0,
+            b: TemperatureInterval::new::<kelvin_interval>(3800.0),
         }
     }
 }

src/timer.rs

@@ -4,9 +4,9 @@ use cortex_m::interrupt::Mutex;
 use cortex_m_rt::exception;
 use stm32f4xx_hal::{
     rcc::Clocks,
-    time::U32Ext,
-    timer::{Timer, Event as TimerEvent},
     stm32::SYST,
+    time::U32Ext,
+    timer::{Event as TimerEvent, Timer},
 };
 
 /// Rate in Hz
@@ -18,7 +18,6 @@ static TIMER_MS: Mutex<RefCell<u32>> = Mutex::new(RefCell::new(0));
 
 /// Setup SysTick exception
 pub fn setup(syst: SYST, clocks: Clocks) {
-    
     let timer = Timer::syst(syst, &clocks);
     let mut countdown = timer.start_count_down(TIMER_RATE.hz());
     countdown.listen(TimerEvent::TimeOut);
@@ -28,18 +27,13 @@ pub fn setup(syst: SYST, clocks: Clocks) {
 #[exception]
 fn SysTick() {
     cortex_m::interrupt::free(|cs| {
-        *TIMER_MS.borrow(cs)
-            .borrow_mut() += TIMER_DELTA;
+        *TIMER_MS.borrow(cs).borrow_mut() += TIMER_DELTA;
     });
 }
 
 /// Obtain current time in milliseconds
 pub fn now() -> u32 {
-    cortex_m::interrupt::free(|cs| {
-        *TIMER_MS.borrow(cs)
-            .borrow()
-            .deref()
-    })
+    cortex_m::interrupt::free(|cs| *TIMER_MS.borrow(cs).borrow().deref())
 }
 
 /// block for at least `amount` milliseconds

src/usb.rs

@@ -1,15 +1,18 @@
-use core::{fmt::{self, Write}, mem::MaybeUninit};
+use core::{
+    fmt::{self, Write},
+    mem::MaybeUninit,
+};
 use cortex_m::interrupt::free;
+use log::{Log, Metadata, Record};
 use stm32f4xx_hal::{
-    otg_fs::{USB, UsbBus as Bus},
+    otg_fs::{UsbBus as Bus, USB},
     stm32::{interrupt, Interrupt, NVIC},
 };
 use usb_device::{
-    class_prelude::{UsbBusAllocator},
+    class_prelude::UsbBusAllocator,
     prelude::{UsbDevice, UsbDeviceBuilder, UsbVidPid},
 };
 use usbd_serial::SerialPort;
-use log::{Record, Log, Metadata};
 
 static mut EP_MEMORY: [u32; 1024] = [0; 1024];
 
@@ -36,8 +39,8 @@ impl State {
             .device_class(usbd_serial::USB_CLASS_CDC)
             .build();
 
-        free(|_| {
-            unsafe { STATE = Some(State { serial, dev }); }
+        free(|_| unsafe {
+            STATE = Some(State { serial, dev });
         });
 
         unsafe {
@@ -94,8 +97,7 @@ impl Write for SerialOutput {
     fn write_str(&mut self, s: &str) -> core::result::Result<(), core::fmt::Error> {
         if let Some(ref mut state) = State::get() {
             for chunk in s.as_bytes().chunks(16) {
-                free(|_| state.serial.write(chunk))
-                    .map_err(|_| fmt::Error)?;
+                free(|_| state.serial.write(chunk)).map_err(|_| fmt::Error)?;
             }
         }
         Ok(())