thermostat/src/channels.rs
2020-09-16 22:22:48 +02:00

390 lines
15 KiB
Rust

use stm32f4xx_hal::hal;
use smoltcp::time::Instant;
use uom::si::{
f64::{ElectricCurrent, ElectricPotential, ElectricalResistance},
electric_potential::{millivolt, volt},
electric_current::ampere,
electrical_resistance::ohm,
ratio::ratio,
};
use log::info;
use crate::{
ad5680,
ad7172,
channel::{Channel, Channel0, Channel1},
channel_state::ChannelState,
command_parser::PwmPin,
pins,
};
pub const CHANNELS: usize = 2;
pub const R_SENSE: f64 = 0.05;
// TODO: -pub
pub struct Channels {
channel0: Channel<Channel0>,
channel1: Channel<Channel1>,
pub adc: ad7172::Adc<pins::AdcSpi, pins::AdcNss>,
/// stm32f4 integrated adc
pins_adc: pins::PinsAdc,
pub pwm: pins::PwmPins,
}
impl Channels {
pub fn new(pins: pins::Pins) -> Self {
let mut adc = ad7172::Adc::new(pins.adc_spi, pins.adc_nss).unwrap();
// Feature not used
adc.set_sync_enable(false).unwrap();
// Setup channels and start ADC
adc.setup_channel(0, ad7172::Input::Ain0, ad7172::Input::Ain1).unwrap();
let adc_calibration0 = adc.get_calibration(0)
.expect("adc_calibration0");
adc.setup_channel(1, ad7172::Input::Ain2, ad7172::Input::Ain3).unwrap();
let adc_calibration1 = adc.get_calibration(1)
.expect("adc_calibration1");
adc.start_continuous_conversion().unwrap();
let mut channel0 = Channel::new(pins.channel0, adc_calibration0);
let mut 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 };
for channel in 0..CHANNELS {
// FIXME: this reads 1.5 V instead of the expected 1.65 V.
// channels.channel_state(channel).vref = channels.read_vref(channel);
channels.calibrate_dac_value(channel);
}
channels
}
pub fn channel_state<I: Into<usize>>(&mut self, channel: I) -> &mut ChannelState {
match channel.into() {
0 => &mut self.channel0.state,
1 => &mut self.channel1.state,
_ => unreachable!(),
}
}
/// ADC input + PID processing
pub fn poll_adc(&mut self, instant: Instant) -> Option<u8> {
self.adc.data_ready().unwrap().map(|channel| {
let data = self.adc.read_data().unwrap();
let dac_value = {
let state = self.channel_state(channel);
state.update(instant, data);
let pid_output = state.update_pid();
if state.pid_engaged {
Some(pid_output)
} else {
None
}
};
if let Some(dac_value) = dac_value {
// Forward PID output to i_set DAC
// TODO:
// self.set_dac(channel.into(), ElectricPotential::new::<volt>(dac_value));
}
channel
})
}
/// i_set DAC
fn get_dac(&mut self, channel: usize) -> (ElectricPotential, ElectricPotential) {
let dac_factor = match channel.into() {
0 => self.channel0.dac_factor,
1 => self.channel1.dac_factor,
_ => unreachable!(),
};
let voltage = self.channel_state(channel).dac_value;
let max = ElectricPotential::new::<volt>(ad5680::MAX_VALUE as f64 / dac_factor);
(voltage, max)
}
pub fn get_i(&mut self, channel: usize) -> (ElectricCurrent, ElectricCurrent) {
let vref = self.channel_state(channel).vref;
let r_sense = ElectricalResistance::new::<ohm>(R_SENSE);
let (voltage, max) = self.get_dac(channel);
let i_tec = (voltage - vref) / (10.0 * r_sense);
let max = (max - vref) / (10.0 * r_sense);
(i_tec, max)
}
/// i_set DAC
fn set_dac(&mut self, channel: usize, voltage: ElectricPotential) -> (ElectricPotential, ElectricPotential) {
let dac_factor = match channel.into() {
0 => self.channel0.dac_factor,
1 => self.channel1.dac_factor,
_ => unreachable!(),
};
let value = (voltage.get::<volt>() * dac_factor) as u32;
let value = match channel {
0 => self.channel0.dac.set(value).unwrap(),
1 => self.channel1.dac.set(value).unwrap(),
_ => unreachable!(),
};
let voltage = ElectricPotential::new::<volt>(value as f64 / dac_factor);
self.channel_state(channel).dac_value = voltage;
let max = ElectricPotential::new::<volt>(ad5680::MAX_VALUE as f64 / dac_factor);
(voltage, max)
}
pub fn set_i(&mut self, channel: usize, i_tec: ElectricCurrent) -> (ElectricCurrent, ElectricCurrent) {
let vref = self.channel_state(channel).vref;
let r_sense = ElectricalResistance::new::<ohm>(R_SENSE);
let voltage = i_tec * 10.0 * r_sense + vref;
let (voltage, max) = self.set_dac(channel, voltage);
let i_tec = (voltage - vref) / (10.0 * r_sense);
let max = (max - vref) / (10.0 * r_sense);
(i_tec, max)
}
pub fn read_dac_feedback(&mut self, channel: usize) -> ElectricPotential {
match channel {
0 => {
let sample = self.pins_adc.convert(
&self.channel0.dac_feedback_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
info!("dac0_fb: {}/{:03X}", mv, sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
1 => {
let sample = self.pins_adc.convert(
&self.channel1.dac_feedback_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
info!("dac1_fb: {}/{:03X}", mv, sample);
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.read_dac_feedback(channel);
loop {
let current = self.read_dac_feedback(channel);
use num_traits::float::Float;
if (current - prev).abs() < tolerance {
return current;
}
prev = current;
}
}
pub fn read_itec(&mut self, channel: usize) -> ElectricPotential {
match channel {
0 => {
let sample = self.pins_adc.convert(
&self.channel0.itec_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
1 => {
let sample = self.pins_adc.convert(
&self.channel1.itec_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
_ => unreachable!(),
}
}
/// should be 1.5V
pub fn read_vref(&mut self, channel: usize) -> ElectricPotential {
match channel {
0 => {
let sample = self.pins_adc.convert(
&self.channel0.vref_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
1 => {
let sample = self.pins_adc.convert(
&self.channel1.vref_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
_ => unreachable!(),
}
}
pub fn read_tec_u_meas(&mut self, channel: usize) -> ElectricPotential {
match channel {
0 => {
let sample = self.pins_adc.convert(
&self.channel0.tec_u_meas_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
1 => {
let sample = self.pins_adc.convert(
&self.channel1.tec_u_meas_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
}
_ => unreachable!(),
}
}
/// Calibrate the I_SET DAC using the DAC_FB ADC pin.
///
/// These loops perform a width-first search for the DAC setting
/// that will produce a `target_voltage`.
pub fn calibrate_dac_value(&mut self, channel: usize) {
let target_voltage = ElectricPotential::new::<volt>(2.5);
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 value in (start_value..=ad5680::MAX_VALUE).step_by(1 << step) {
match channel {
0 => {
self.channel0.dac.set(value).unwrap();
}
1 => {
self.channel1.dac.set(value).unwrap();
}
_ => unreachable!(),
}
let dac_feedback = self.read_dac_feedback_until_stable(channel, ElectricPotential::new::<volt>(0.001));
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;
let dac_factor = value as f64 / dac_feedback.get::<volt>();
match channel {
0 => self.channel0.dac_factor = dac_factor,
1 => self.channel1.dac_factor = dac_factor,
_ => unreachable!(),
}
}
prev_value = value;
}
}
// Reset
self.set_dac(channel, ElectricPotential::new::<volt>(0.0));
}
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, ElectricPotential) {
let vref = self.channel_state(channel).vref;
let duty = self.get_pwm(channel, PwmPin::MaxV);
(duty * 4.0 * vref, 4.0 * vref)
}
pub fn get_max_i_pos(&mut self, channel: usize) -> (ElectricCurrent, ElectricCurrent) {
let vref = self.channel_state(channel).vref;
let scale = vref / ElectricPotential::new::<volt>(3.0) / ElectricCurrent::new::<ampere>(1.0);
let duty = self.get_pwm(channel, PwmPin::MaxIPos);
(duty / scale, 1.0 / scale)
}
pub fn get_max_i_neg(&mut self, channel: usize) -> (ElectricCurrent, ElectricCurrent) {
let vref = self.channel_state(channel).vref;
let scale = vref / ElectricPotential::new::<volt>(3.0) / ElectricCurrent::new::<ampere>(1.0);
let duty = self.get_pwm(channel, PwmPin::MaxINeg);
(duty / scale, 1.0 / scale)
}
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 {
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!(),
}
}
pub fn set_max_v(&mut self, channel: usize, max_v: ElectricPotential) -> (ElectricPotential, ElectricPotential) {
let vref = self.channel_state(channel).vref;
let duty = (max_v / 4.0 / vref).get::<ratio>();
let duty = self.set_pwm(channel, PwmPin::MaxV, duty);
(duty * 4.0 * vref, 4.0 * vref)
}
pub fn set_max_i_pos(&mut self, channel: usize, max_i_pos: ElectricCurrent) -> (ElectricCurrent, ElectricCurrent) {
let vref = self.channel_state(channel).vref;
let scale = vref / ElectricPotential::new::<volt>(3.0) / ElectricCurrent::new::<ampere>(1.0);
let duty = (max_i_pos * scale).get::<ratio>();
let duty = self.set_pwm(channel, PwmPin::MaxIPos, duty);
(duty / scale, 1.0 / scale)
}
pub fn set_max_i_neg(&mut self, channel: usize, max_i_neg: ElectricCurrent) -> (ElectricCurrent, ElectricCurrent) {
let vref = self.channel_state(channel).vref;
let scale = vref / ElectricPotential::new::<volt>(3.0) / ElectricCurrent::new::<ampere>(1.0);
let duty = (max_i_neg * scale).get::<ratio>();
let duty = self.set_pwm(channel, PwmPin::MaxINeg, duty);
(duty / scale, 1.0 / scale)
}
}