Fix device signature constants, adc dma example (#97)

Author: no111u3

examples/adc-continious-dma.rs

@@ -1,7 +1,7 @@
 #![no_std]
 #![no_main]
 
-use cortex_m_rt::entry;
+mod utils;
 
 use crate::hal::{
     adc::{
@@ -16,10 +16,11 @@ use crate::hal::{
 };
 use stm32g4xx_hal as hal;
 
-use log::info;
+use stm32g4xx_hal::adc::config;
+use stm32g4xx_hal::signature::{VrefCal, VDDA_CALIB};
 
-#[macro_use]
-mod utils;
+use cortex_m_rt::entry;
+use utils::logger::info;
 
 #[entry]
 fn main() -> ! {
@@ -51,13 +52,15 @@ fn main() -> ! {
         .claim(ClockSource::SystemClock, &rcc, &mut delay, true);
 
     adc.enable_temperature(&dp.ADC12_COMMON);
+    adc.enable_vref(&dp.ADC12_COMMON);
     adc.set_continuous(Continuous::Continuous);
     adc.reset_sequence();
     adc.configure_channel(&pa0, Sequence::One, SampleTime::Cycles_640_5);
     adc.configure_channel(&Temperature, Sequence::Two, SampleTime::Cycles_640_5);
+    adc.configure_channel(&Vref, Sequence::Three, SampleTime::Cycles_640_5);
 
     info!("Setup DMA");
-    let first_buffer = cortex_m::singleton!(: [u16; 10] = [0; 10]).unwrap();
+    let first_buffer = cortex_m::singleton!(: [u16; 15] = [0; 15]).unwrap();
     let mut transfer = streams.0.into_circ_peripheral_to_memory_transfer(
         adc.enable_dma(AdcDma::Continuous),
         &mut first_buffer[..],
@@ -67,7 +70,7 @@ fn main() -> ! {
     transfer.start(|adc| adc.start_conversion());
 
     loop {
-        let mut b = [0_u16; 4];
+        let mut b = [0_u16; 6];
         let r = transfer.read_exact(&mut b);
         assert!(
             !transfer.get_overrun_flag(),
@@ -77,9 +80,18 @@ fn main() -> ! {
         info!("read: {}", r);
         assert!(r == b.len());
 
-        let millivolts = Vref::sample_to_millivolts((b[0] + b[2]) / 2);
-        info!("pa3: {}mV", millivolts);
-        let temp = Temperature::temperature_to_degrees_centigrade((b[1] + b[3]) / 2);
-        info!("temp: {}℃C", temp); // Note: Temperature seems quite low...
+        let vdda = VDDA_CALIB * VrefCal::get().read() as u32 / ((b[2] + b[5]) / 2) as u32;
+
+        info!("vdda: {}mV", vdda);
+
+        let millivolts =
+            Vref::sample_to_millivolts_ext((b[0] + b[3]) / 2, vdda, config::Resolution::Twelve);
+        info!("pa0: {}mV", millivolts);
+        let vref =
+            Vref::sample_to_millivolts_ext((b[2] + b[5]) / 2, vdda, config::Resolution::Twelve);
+        info!("vref: {}mV", vref);
+        let raw_temp = (((b[1] + b[4]) / 2) as f32 * (vdda as f32 / 3000.0)) as u16;
+        let temp = Temperature::temperature_to_degrees_centigrade(raw_temp);
+        info!("temp: {}°C", temp);
     }
 }

src/adc.rs

@@ -15,7 +15,7 @@ use crate::{
     gpio::*,
     opamp,
     rcc::{Enable, Rcc, Reset},
-    signature::{VtempCal110, VtempCal30, VDDA_CALIB},
+    signature::{VtempCal130, VtempCal30, VDDA_CALIB},
     stm32,
 };
 use core::fmt;
@@ -63,7 +63,7 @@ impl Temperature {
     /// Convert a raw sample from `Temperature` to deg C
     #[inline(always)]
     pub fn temperature_to_degrees_centigrade(sample: u16) -> f32 {
-        ((110.0 - 30.0) / (VtempCal110::get().read() as f32 - VtempCal30::get().read() as f32)
+        ((130.0 - 30.0) / (VtempCal130::get().read() as f32 - VtempCal30::get().read() as f32)
             * (sample as f32 - VtempCal30::get().read() as f32))
             + 30.0
     }

src/signature.rs

@@ -5,7 +5,7 @@
 use core::str::from_utf8_unchecked;
 
 /// This is the test voltage, in millivolts of the calibration done at the factory
-pub const VDDA_CALIB: u32 = 3300;
+pub const VDDA_CALIB: u32 = 3000;
 
 macro_rules! define_ptr_type {
     ($name: ident, $ptr: expr) => {
@@ -98,13 +98,13 @@ impl VtempCal30 {
     }
 }
 
-/// A temperature reading taken at 110°C stored at the factory
+/// A temperature reading taken at 130°C stored at the factory
 #[derive(Debug)]
 #[repr(C)]
-pub struct VtempCal110(u16);
-define_ptr_type!(VtempCal110, 0x1FFF_75CA);
+pub struct VtempCal130(u16);
+define_ptr_type!(VtempCal130, 0x1FFF_75CA);
 
-impl VtempCal110 {
+impl VtempCal130 {
     /// Read calibration value
     pub fn read(&self) -> u16 {
         self.0