add units::Volts, use for stm32f4 adc

src/channels.rs

@@ -5,6 +5,7 @@ use crate::{
     channel::{Channel, Channel0, Channel1},
     channel_state::ChannelState,
     pins,
+    units::Volts,
 };
 
 pub const CHANNELS: usize = 2;
@@ -82,30 +83,46 @@ impl Channels {
         }
     }
 
-    pub fn read_dac_loopback(&mut self, channel: usize) -> u16 {
+    pub fn read_dac_loopback(&mut self, channel: usize) -> Volts {
         match channel {
-            0 => self.channel0.adc.convert(
+            0 => {
+                let sample = self.channel0.adc.convert(
                     &self.channel0.dac_loopback_pin,
                     stm32f4xx_hal::adc::config::SampleTime::Cycles_480
-            ),
+                );
-            1 => self.channel1.adc.convert(
+                let mv = self.channel0.adc.sample_to_millivolts(sample);
+                Volts(mv as f64 / 1000.0)
+            }
+            1 => {
+                let sample = self.channel1.adc.convert(
                     &self.channel1.dac_loopback_pin,
                     stm32f4xx_hal::adc::config::SampleTime::Cycles_480
-            ),
+                );
+                let mv = self.channel1.adc.sample_to_millivolts(sample);
+                Volts(mv as f64 / 1000.0)
+            }
             _ => unreachable!(),
         }
     }
 
-    pub fn read_itec(&mut self, channel: usize) -> u16 {
+    pub fn read_itec(&mut self, channel: usize) -> Volts {
         match channel {
-            0 => self.channel0.adc.convert(
+            0 => {
+                let sample = self.channel0.adc.convert(
                     &self.channel0.itec_pin,
                     stm32f4xx_hal::adc::config::SampleTime::Cycles_480
-            ),
+                );
-            1 => self.channel1.adc.convert(
+                let mv = self.channel0.adc.sample_to_millivolts(sample);
+                Volts(mv as f64 / 1000.0)
+            }
+            1 => {
+                let sample = self.channel1.adc.convert(
                     &self.channel1.itec_pin,
                     stm32f4xx_hal::adc::config::SampleTime::Cycles_480
-            ),
+                );
+                let mv = self.channel1.adc.sample_to_millivolts(sample);
+                Volts(mv as f64 / 1000.0)
+            }
             _ => unreachable!(),
         }
     }

src/main.rs

@@ -42,6 +42,7 @@ use session::{Session, SessionOutput};
 mod command_parser;
 use command_parser::{Command, ShowCommand, PwmPin};
 mod timer;
+mod units;
 mod pid;
 mod steinhart_hart;
 mod channels;
@@ -143,14 +144,13 @@ fn main() -> ! {
                                         if let Some(adc_data) = channels.channel_state(channel).adc_data {
                                             let dac_loopback = channels.read_dac_loopback(channel);
                                             let itec = channels.read_itec(channel);
-                                            let dcc_u = 5.0;
+                                            let itec_u = itec.0;
-                                            let itec_u = dcc_u * (itec as f64) / (0xFFF as f64);
                                             let tec_u = (itec_u - 1.5) / 8.0;
                                             let tec_r = 5.0;
                                             let tec_i = tec_u / tec_r;
                                             let state = channels.channel_state(channel);
                                             let _ = writeln!(
-                                                socket, "t={} raw{}=0x{:06X} dac_loopback=0x{:X} itec=0x{:X} tec={:.2}V/{:.2}A",
+                                                socket, "t={} raw{}=0x{:06X} dac_loopback={} itec={} tec={:.3}V/{:.3}A",
                                                 state.adc_time, channel, adc_data,
                                                 dac_loopback, itec,
                                                 tec_u, tec_i,

src/units.rs

@@ -0,0 +1,10 @@
+use core::fmt;
+
+#[derive(Debug, Clone, PartialEq, PartialOrd)]
+pub struct Volts(pub f64);
+
+impl fmt::Display for Volts {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{:.3}V", self.0)
+    }
+}