thermostat/src/channels.rs

620 lines
22 KiB
Rust

use serde::{Serialize, Serializer};
use smoltcp::time::Instant;
use stm32f4xx_hal::hal;
use uom::si::{
f64::{ElectricCurrent, ElectricPotential, ElectricalResistance},
electric_potential::{millivolt, volt},
electric_current::ampere,
electrical_resistance::ohm,
ratio::ratio,
thermodynamic_temperature::degree_celsius,
};
use crate::{
ad5680,
ad7172,
channel::{Channel, Channel0, Channel1},
channel_state::ChannelState,
command_parser::{CenterPoint, PwmPin},
pins,
steinhart_hart,
};
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 channel0 = Channel::new(pins.channel0, adc_calibration0);
let 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 {
channels.channel_state(channel).vref = channels.read_vref(channel);
channels.calibrate_dac_value(channel);
channels.set_i(channel, ElectricCurrent::new::<ampere>(0.0));
}
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 state = self.channel_state(channel);
state.update(instant, data);
match state.update_pid() {
Some(pid_output) if state.pid_engaged => {
// Forward PID output to i_set DAC
self.set_i(channel.into(), ElectricCurrent::new::<ampere>(pid_output));
self.power_up(channel);
}
None if state.pid_engaged => {
self.power_down(channel);
}
_ => {}
}
channel
})
}
/// calculate the TEC i_set centerpoint
pub fn get_center(&mut self, channel: usize) -> ElectricPotential {
match self.channel_state(channel).center {
CenterPoint::Vref => {
let vref = self.read_vref(channel);
self.channel_state(channel).vref = vref;
vref
},
CenterPoint::Override(center_point) =>
ElectricPotential::new::<volt>(center_point.into()),
}
}
/// 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 center_point = self.get_center(channel);
let r_sense = ElectricalResistance::new::<ohm>(R_SENSE);
let (voltage, max) = self.get_dac(channel);
let i_tec = (voltage - center_point) / (10.0 * r_sense);
let max = (max - center_point) / (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 center_point = self.get_center(channel);
let r_sense = ElectricalResistance::new::<ohm>(R_SENSE);
let voltage = i_tec * 10.0 * r_sense + center_point;
let (voltage, max) = self.set_dac(channel, voltage);
let i_tec = (voltage - center_point) / (10.0 * r_sense);
let max = (max - center_point) / (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);
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);
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);
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 breadth-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));
}
// power up TEC
pub fn power_up<I: Into<usize>>(&mut self, channel: I) {
match channel.into() {
0 => self.channel0.power_up(),
1 => self.channel1.power_up(),
_ => unreachable!(),
}
}
// power down TEC
pub fn power_down<I: Into<usize>>(&mut self, channel: I) {
match channel.into() {
0 => self.channel0.power_down(),
1 => self.channel1.power_down(),
_ => unreachable!(),
}
}
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 max = 4.0 * vref;
let duty = self.get_pwm(channel, PwmPin::MaxV);
(duty * max, max)
}
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);
(duty * max, max)
}
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);
(duty * max, max)
}
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 max = 4.0 * vref;
let duty = (max_v / max).get::<ratio>();
let duty = self.set_pwm(channel, PwmPin::MaxV, duty);
(duty * max, max)
}
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 / max).get::<ratio>();
let duty = 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 / max).get::<ratio>();
let duty = self.set_pwm(channel, PwmPin::MaxINeg, duty);
(duty * max, max)
}
pub fn report(&mut self, channel: usize) -> Report {
let vref = self.channel_state(channel).vref;
let (i_set, _) = self.get_i(channel);
let i_tec = self.read_itec(channel);
let tec_i = (i_tec - vref) / ElectricalResistance::new::<ohm>(0.4);
let (dac_value, _) = self.get_dac(channel);
let state = self.channel_state(channel);
let pid_output = state.pid.last_output.map(|last_output|
ElectricCurrent::new::<ampere>(last_output)
);
Report {
channel,
time: state.adc_time.total_millis(),
adc: state.get_adc(),
sens: state.get_sens(),
temperature: state.get_temperature()
.map(|temperature| temperature.get::<degree_celsius>()),
pid_engaged: state.pid_engaged,
i_set,
vref,
dac_value,
dac_feedback: self.read_dac_feedback(channel),
i_tec,
tec_i,
tec_u_meas: self.read_tec_u_meas(channel),
pid_output,
}
}
pub fn pwm_summary(&mut self, channel: usize) -> PwmSummary {
PwmSummary {
channel,
center: CenterPointJson(self.channel_state(channel).center.clone()),
i_set: self.get_i(channel).into(),
max_v: self.get_max_v(channel).into(),
max_i_pos: self.get_max_i_pos(channel).into(),
max_i_neg: self.get_max_i_neg(channel).into(),
}
}
pub fn postfilter_summary(&mut self, channel: usize) -> PostFilterSummary {
let rate = self.adc.get_postfilter(channel as u8).unwrap()
.and_then(|filter| filter.output_rate());
PostFilterSummary { channel, rate }
}
pub fn steinhart_hart_summary(&mut self, channel: usize) -> SteinhartHartSummary {
let params = self.channel_state(channel).sh.clone();
SteinhartHartSummary { channel, params }
}
}
type JsonBuffer = heapless::Vec<u8, heapless::consts::U512>;
#[derive(Serialize)]
pub struct Report {
channel: usize,
time: i64,
adc: Option<ElectricPotential>,
sens: Option<ElectricalResistance>,
temperature: Option<f64>,
pid_engaged: bool,
i_set: ElectricCurrent,
vref: ElectricPotential,
dac_value: ElectricPotential,
dac_feedback: ElectricPotential,
i_tec: ElectricPotential,
tec_i: ElectricCurrent,
tec_u_meas: ElectricPotential,
pid_output: Option<ElectricCurrent>,
}
impl Report {
pub fn to_json(&self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
serde_json_core::to_vec(self)
}
}
pub struct CenterPointJson(CenterPoint);
// used in JSON encoding, not for config
impl Serialize for CenterPointJson {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match self.0 {
CenterPoint::Vref =>
serializer.serialize_str("vref"),
CenterPoint::Override(vref) =>
serializer.serialize_f32(vref),
}
}
}
#[derive(Serialize)]
pub struct PwmSummaryField<T: Serialize> {
value: T,
max: T,
}
impl<T: Serialize> From<(T, T)> for PwmSummaryField<T> {
fn from((value, max): (T, T)) -> Self {
PwmSummaryField { value, max }
}
}
#[derive(Serialize)]
pub struct PwmSummary {
channel: usize,
center: CenterPointJson,
i_set: PwmSummaryField<ElectricCurrent>,
max_v: PwmSummaryField<ElectricPotential>,
max_i_pos: PwmSummaryField<ElectricCurrent>,
max_i_neg: PwmSummaryField<ElectricCurrent>,
}
impl PwmSummary {
pub fn to_json(&self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
serde_json_core::to_vec(self)
}
}
#[derive(Serialize)]
pub struct PostFilterSummary {
channel: usize,
rate: Option<f32>,
}
impl PostFilterSummary {
pub fn to_json(&self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
serde_json_core::to_vec(self)
}
}
#[derive(Serialize)]
pub struct SteinhartHartSummary {
channel: usize,
params: steinhart_hart::Parameters,
}
impl SteinhartHartSummary {
pub fn to_json(&self) -> Result<JsonBuffer, serde_json_core::ser::Error> {
serde_json_core::to_vec(self)
}
}
#[cfg(test)]
mod test {
use super::*;
#[test]
fn report_to_json() {
// `/ 1.1` results in values with a really long serialization
let report = Report {
channel: 0,
time: 3200,
adc: Some(ElectricPotential::new::<volt>(0.65 / 1.1)),
sens: Some(ElectricalResistance::new::<ohm>(10000.0 / 1.1)),
temperature: Some(30.0 / 1.1),
pid_engaged: false,
i_set: ElectricCurrent::new::<ampere>(0.5 / 1.1),
vref: ElectricPotential::new::<volt>(1.5 / 1.1),
dac_value: ElectricPotential::new::<volt>(2.0 / 1.1),
dac_feedback: ElectricPotential::new::<volt>(2.0 / 1.1),
i_tec: ElectricPotential::new::<volt>(2.0 / 1.1),
tec_i: ElectricCurrent::new::<ampere>(0.2 / 1.1),
tec_u_meas: ElectricPotential::new::<volt>(2.0 / 1.1),
pid_output: Some(ElectricCurrent::new::<ampere>(0.5 / 1.1)),
};
let buf = report.to_json().unwrap();
assert_eq!(buf[0], b'{');
assert_eq!(buf[buf.len() - 1], b'}');
}
#[test]
fn pwm_summary_to_json() {
let value = 1.0 / 1.1;
let max = 5.0 / 1.1;
let pwm_summary = PwmSummary {
channel: 0,
center: CenterPointJson(CenterPoint::Vref),
i_set: PwmSummaryField {
value: ElectricCurrent::new::<ampere>(value),
max: ElectricCurrent::new::<ampere>(max),
},
max_v: PwmSummaryField {
value: ElectricPotential::new::<volt>(value),
max: ElectricPotential::new::<volt>(max),
},
max_i_pos: PwmSummaryField {
value: ElectricCurrent::new::<ampere>(value),
max: ElectricCurrent::new::<ampere>(max),
},
max_i_neg: PwmSummaryField {
value: ElectricCurrent::new::<ampere>(value),
max: ElectricCurrent::new::<ampere>(max),
},
};
let buf = pwm_summary.to_json().unwrap();
assert_eq!(buf[0], b'{');
assert_eq!(buf[buf.len() - 1], b'}');
}
}