README: Document swap status in report

add swap status to the report
Signed-off-by: Egor Savkin <es@m-labs.hk>
2024-09-23 18:04:06 +08:00 · 2024-09-23 18:04:06 +08:00 · 2024-09-23 18:04:04 +08:00 · 2024-09-19 10:08:58 +08:00 · 2024-09-19 10:06:45 +08:00 · 2024-09-16 18:14:47 +08:00
7 changed files with 71 additions and 45 deletions
--- a/.gitignore
+++ b/.gitignore
@ -1,2 +1,5 @@
 target/
 result
+*.bin
+
+__pycache__/
--- a/README.md
+++ b/README.md
@ -256,21 +256,22 @@ Use the bare `report` command to obtain a single report. Enable
 continuous reporting with `report mode on`. Reports are JSON objects
 with the following keys.

-| Key            | Unit            | Description                                          |
-| ---            | :---:           | ---                                                  |
-| `channel`      | Integer         | Channel `0`, or `1`                                  |
-| `time`         | Seconds         | Temperature measurement time                         |
-| `adc`          | Volts           | AD7172 input                                         |
-| `sens`         | Ohms            | Thermistor resistance derived from `adc`             |
-| `temperature`  | Degrees Celsius | Steinhart-Hart conversion result derived from `sens` |
-| `pid_engaged`  | Boolean         | `true` if in closed-loop mode                        |
-| `i_set`        | Amperes         | TEC output current                                   |
-| `dac_value`    | Volts           | AD5680 output derived from `i_set`                   |
-| `dac_feedback` | Volts           | ADC measurement of the AD5680 output                 |
-| `i_tec`        | Volts           | MAX1968 TEC current monitor                          |
-| `tec_i`        | Amperes         | TEC output current feedback derived from `i_tec`     |
-| `tec_u_meas`   | Volts           | Measurement of the voltage across the TEC            |
-| `pid_output`   | Amperes         | PID control output                                   |
+| Key               | Unit            | Description                                                        |
+| ---               | :---:           | ---                                                                |
+| `channel`         | Integer         | Channel `0`, or `1`                                                |
+| `time`            | Seconds         | Temperature measurement time                                       |
+| `adc`             | Volts           | AD7172 input                                                       |
+| `sens`            | Ohms            | Thermistor resistance derived from `adc`                           |
+| `temperature`     | Degrees Celsius | Steinhart-Hart conversion result derived from `sens`               |
+| `pid_engaged`     | Boolean         | `true` if in closed-loop mode                                      |
+| `current_swapped` | Boolean         | `true` if TEC current direction is swapped relative to front panel |
+| `i_set`           | Amperes         | TEC output current                                                 |
+| `dac_value`       | Volts           | AD5680 output derived from `i_set`                                 |
+| `dac_feedback`    | Volts           | ADC measurement of the AD5680 output                               |
+| `i_tec`           | Volts           | MAX1968 TEC current monitor                                        |
+| `tec_i`           | Amperes         | TEC output current feedback derived from `i_tec`                   |
+| `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].

--- a/flake.nix
+++ b/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
          ]);
--- a/src/channels.rs
+++ b/src/channels.rs
@ -22,6 +22,7 @@ use crate::{
    pins::{self, Channel0VRef, Channel1VRef},
    steinhart_hart,
 };
+use crate::timer::sleep;

 pub enum PinsAdcReadTarget {
    VREF,
@ -152,11 +153,13 @@ impl Channels {
    }

    pub fn set_i(&mut self, channel: usize, i_set: ElectricCurrent) -> ElectricCurrent {
-        let mut i_set = i_set.min(MAX_TEC_I).max(-MAX_TEC_I);
+        let i_set = i_set.min(MAX_TEC_I).max(-MAX_TEC_I);
        self.channel_state(channel).i_set = i_set;
-        if self.channel_state(channel).polarity_swapped {
-            i_set = -i_set;
-        }
+        let negate = if self.channel_state(channel).polarity_swapped {
+            -1.0
+        } else {
+            1.0
+        };
        let vref_meas = match channel.into() {
            0 => self.channel0.vref_meas,
            1 => self.channel1.vref_meas,
@ -164,9 +167,9 @@ impl Channels {
        };
        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);
+        let i_set = negate * (voltage - center_point) / (10.0 * r_sense);
        i_set
    }

@ -272,17 +275,6 @@ impl Channels {
        }
    }

-    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;
-        }
-    }
-
    /// Calibrates the DAC output to match vref of the MAX driver to reduce zero-current offset of the MAX driver output.
    ///
    /// The thermostat DAC applies a control voltage signal to the CTLI pin of MAX driver chip to control its output current.
@ -309,7 +301,7 @@ impl Channels {
        let mut start_value = 1;
        let mut best_error = ElectricPotential::new::<volt>(100.0);

-        for step in (0..18).rev() {
+        for step in (5..18).rev() {
            let mut prev_value = start_value;
            for value in (start_value..=ad5680::MAX_VALUE).step_by(1 << step) {
                match channel {
@ -321,8 +313,9 @@ 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;
@ -398,13 +391,21 @@ impl Channels {

    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);
+        let duty = if self.channel_state(channel).polarity_swapped {
+            self.get_pwm(channel, PwmPin::MaxINeg)
+        } else {
+            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);
+        let duty = if self.channel_state(channel).polarity_swapped {
+            self.get_pwm(channel, PwmPin::MaxIPos)
+        } else {
+            self.get_pwm(channel, PwmPin::MaxINeg)
+        };
        (duty * max, MAX_TEC_I)
    }

@ -460,17 +461,38 @@ impl Channels {
    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);
+        let duty = if self.channel_state(channel).polarity_swapped {
+            self.set_pwm(channel, PwmPin::MaxINeg, duty)
+        } else {
+            self.set_pwm(channel, PwmPin::MaxIPos, duty)
+        };
        (duty * max, max)
    }

    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);
+        let duty = if self.channel_state(channel).polarity_swapped {
+            self.set_pwm(channel, PwmPin::MaxIPos, duty)
+        } else {
+            self.set_pwm(channel, PwmPin::MaxINeg, duty)
+        };
        (duty * max, max)
    }

+    pub fn swap_polarity(&mut self, channel: usize, swapped: bool) {
+        if self.channel_state(channel).polarity_swapped != swapped {
+            let i_set = self.channel_state(channel).i_set;
+            let max_i_pos = self.get_max_i_pos(channel).0;
+            let max_i_neg = self.get_max_i_neg(channel).0;
+
+            self.channel_state(channel).polarity_swapped = swapped;
+            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_tec = self.adc_read(channel, PinsAdcReadTarget::ITec, 16);
--- a/src/command_handler.rs
+++ b/src/command_handler.rs
@ -182,10 +182,7 @@ impl Handler {
    }

    fn swap_polarity (socket: &mut TcpSocket, channels: &mut Channels, channel: usize, swapped: bool) -> Result<Handler, Error> {
-        channels.channel_state(channel).polarity_swapped = swapped;
-        let channel_state = channels.channel_state(channel);
-        let i_set = channel_state.i_set;
-        channels.set_i(channel, i_set);
+        channels.swap_polarity(channel, swapped);
        send_line(socket, b"{}");
        Ok(Handler::Handled)
    }
--- a/src/config.rs
+++ b/src/config.rs
@ -20,6 +20,7 @@ pub struct ChannelConfig {
    pid_target: f32,
    pid_engaged: bool,
    i_set: ElectricCurrent,
+    polarity_swapped: bool,
    sh: steinhart_hart::Parameters,
    pwm: PwmLimits,
    /// uses variant `PostFilter::Invalid` instead of `None` to save space
@ -45,7 +46,8 @@ impl ChannelConfig {
            pid: state.pid.parameters.clone(),
            pid_target: state.pid.target as f32,
            pid_engaged: state.pid_engaged,
-            i_set: i_set,
+            i_set,
+            polarity_swapped: state.polarity_swapped,
            sh: state.sh.clone(),
            pwm,
            adc_postfilter,
@ -68,6 +70,7 @@ impl ChannelConfig {
        };
        let _ = channels.adc.set_postfilter(channel as u8, adc_postfilter);
        let _ = channels.set_i(channel, self.i_set);
+        channels.swap_polarity(channel, self.polarity_swapped);
    }
 }

--- a/src/main.rs
+++ b/src/main.rs
@ -58,7 +58,7 @@ mod hw_rev;

 const HSE: MegaHertz = MegaHertz(8);
 #[cfg(not(feature = "semihosting"))]
-const WATCHDOG_INTERVAL: u32 = 1_000;
+const WATCHDOG_INTERVAL: u32 = 2_000;
 #[cfg(feature = "semihosting")]
 const WATCHDOG_INTERVAL: u32 = 30_000;
Author	SHA1	Message	Date
atse	0940520ded	README: Document swap status in report	2024-09-23 18:04:06 +08:00
Egor Savkin	2c6b8e8186	add swap status to the report Signed-off-by: Egor Savkin <es@m-labs.hk>	2024-09-23 18:04:06 +08:00
atse	8f8baa0cee	Add command for flipping output polarity Effectively switches all values related to the directionality of current through the TEC, including current maximums. The swapped status is stored in the flash store. To swap current directions, use the command "pwm <ch> polarity_swapped <bool>", where <bool> is true when TEC current direction is reversed from the front panel markings. This is needed for IDC cable connections, since the IDC connector and front panel connectors have flipped polarities.	2024-09-23 18:04:04 +08:00
atse	ae4bea0c8a	gitignore: Ignore .bin files and __pycache__	2024-09-19 10:08:58 +08:00
atse	1f2de942e4	flake: Add rlwrap to devShell	2024-09-19 10:06:45 +08:00
atse	1041d3ecbb	Improve the VREF calibration routine * Fix wrong calibration of VREF on startup. Caused new v2.2.2 boards to wrongly calibrate the zero-point to ~2.2 V instead of 1.5 V. * Fix bootloop on some boards. * Adjust watchdog interval accordingly.	2024-09-16 18:14:47 +08:00