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Fix the calibration sequence

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This fixes a wrong calibration of VREF on startup which wrongly
initiated current through TEC to be over ~1 A on some new v2.2.2 boards.
This commit is contained in:
atse 2024-09-16 17:32:58 +08:00
parent c6040899dd
commit bf9a1488ec
2 changed files with 8 additions and 17 deletions
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17
src/channels.rs
View File

@ -22,6 +22,7 @@ use crate::{
pins::{self, Channel0VRef, Channel1VRef},
steinhart_hart,
};
use crate::timer::sleep;
pub enum PinsAdcReadTarget {
VREF,
@ -269,17 +270,6 @@ 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.
@ -306,7 +296,7 @@ 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 {
@ -318,8 +308,9 @@ 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;

8
src/main.rs
View File

@ -113,10 +113,6 @@ fn main() -> ! {
.pclk2(64.mhz())
.freeze();
let mut wd = IndependentWatchdog::new(dp.IWDG);
wd.start(WATCHDOG_INTERVAL.ms());
wd.feed();
timer::setup(cp.SYST, clocks);
let (pins, mut leds, mut eeprom, eth_pins, usb, fan, hwrev, hw_settings) = Pins::setup(
@ -150,6 +146,10 @@ fn main() -> ! {
}
}
let mut wd = IndependentWatchdog::new(dp.IWDG);
wd.start(WATCHDOG_INTERVAL.ms());
wd.feed();
let mut fan_ctrl = FanCtrl::new(fan, hw_settings);
// default net config: