Add averaging filter on the pin_adc readings

- Adapted from Kirdy Firmware
- Can reduce the i_tec readings noise dispersion
This commit is contained in:
linuswck 2024-05-02 16:47:36 +08:00
parent 9fce19a418
commit 1fcfe41a63
1 changed files with 106 additions and 96 deletions

View File

@ -22,6 +22,13 @@ use crate::{
steinhart_hart, steinhart_hart,
}; };
pub enum PinsAdcReadTarget {
VREF,
DacVfb,
ITec,
VTec,
}
pub const CHANNELS: usize = 2; pub const CHANNELS: usize = 2;
pub const R_SENSE: f64 = 0.05; pub const R_SENSE: f64 = 0.05;
@ -102,7 +109,7 @@ impl Channels {
pub fn get_center(&mut self, channel: usize) -> ElectricPotential { pub fn get_center(&mut self, channel: usize) -> ElectricPotential {
match self.channel_state(channel).center { match self.channel_state(channel).center {
CenterPoint::Vref => CenterPoint::Vref =>
self.read_vref(channel), self.adc_read(channel, PinsAdcReadTarget::VREF, 8),
CenterPoint::Override(center_point) => CenterPoint::Override(center_point) =>
ElectricPotential::new::<volt>(center_point.into()), ElectricPotential::new::<volt>(center_point.into()),
} }
@ -151,32 +158,112 @@ impl Channels {
i_set i_set
} }
pub fn read_dac_feedback(&mut self, channel: usize) -> ElectricPotential { /// AN4073: ADC Reading Dispersion can be reduced through Averaging
pub fn adc_read(&mut self, channel: usize, adc_read_target: PinsAdcReadTarget, avg_pt: u16) -> ElectricPotential {
let mut sample: u32 = 0;
match channel { match channel {
0 => { 0 => {
let sample = self.pins_adc.convert( sample = match adc_read_target {
&self.channel0.dac_feedback_pin, PinsAdcReadTarget::VREF => {
stm32f4xx_hal::adc::config::SampleTime::Cycles_480 match &self.channel0.vref_pin {
); Channel0VRef::Analog(vref_pin) => {
let mv = self.pins_adc.sample_to_millivolts(sample); for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(vref_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
},
Channel0VRef::Disabled(_) => {2048 as u32}
}
}
PinsAdcReadTarget::DacVfb => {
for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(&self.channel0.dac_feedback_pin,stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
}
PinsAdcReadTarget::ITec => {
for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(&self.channel0.itec_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
}
PinsAdcReadTarget::VTec => {
for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(&self.channel0.tec_u_meas_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
}
};
let mv = self.pins_adc.sample_to_millivolts(sample as u16);
ElectricPotential::new::<millivolt>(mv as f64) ElectricPotential::new::<millivolt>(mv as f64)
} }
1 => { 1 => {
let sample = self.pins_adc.convert( sample = match adc_read_target {
&self.channel1.dac_feedback_pin, PinsAdcReadTarget::VREF => {
stm32f4xx_hal::adc::config::SampleTime::Cycles_480 match &self.channel1.vref_pin {
); Channel1VRef::Analog(vref_pin) => {
let mv = self.pins_adc.sample_to_millivolts(sample); for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(vref_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
},
Channel1VRef::Disabled(_) => {2048 as u32}
}
}
PinsAdcReadTarget::DacVfb => {
for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(&self.channel1.dac_feedback_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
}
PinsAdcReadTarget::ITec => {
for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(&self.channel1.itec_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
}
PinsAdcReadTarget::VTec => {
for _ in (0..avg_pt).rev() {
sample += self
.pins_adc
.convert(&self.channel1.tec_u_meas_pin, stm32f4xx_hal::adc::config::SampleTime::Cycles_480)
as u32;
}
sample / avg_pt as u32
}
};
let mv = self.pins_adc.sample_to_millivolts(sample as u16);
ElectricPotential::new::<millivolt>(mv as f64) ElectricPotential::new::<millivolt>(mv as f64)
} }
_ => unreachable!(), _ => unreachable!()
} }
} }
pub fn read_dac_feedback_until_stable(&mut self, channel: usize, tolerance: ElectricPotential) -> ElectricPotential { pub fn read_dac_feedback_until_stable(&mut self, channel: usize, tolerance: ElectricPotential) -> ElectricPotential {
let mut prev = self.read_dac_feedback(channel); let mut prev = self.adc_read(channel, PinsAdcReadTarget::DacVfb, 1);
loop { loop {
let current = self.read_dac_feedback(channel); let current = self.adc_read(channel, PinsAdcReadTarget::DacVfb, 1);
if (current - prev).abs() < tolerance { if (current - prev).abs() < tolerance {
return current; return current;
} }
@ -184,83 +271,6 @@ impl Channels {
} }
} }
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 => {
match &self.channel0.vref_pin {
Channel0VRef::Analog(vref_pin) => {
let sample = self.pins_adc.convert(
vref_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
},
Channel0VRef::Disabled(_) => ElectricPotential::new::<volt>(1.5)
}
}
1 => {
match &self.channel1.vref_pin {
Channel1VRef::Analog(vref_pin) => {
let sample = self.pins_adc.convert(
vref_pin,
stm32f4xx_hal::adc::config::SampleTime::Cycles_480
);
let mv = self.pins_adc.sample_to_millivolts(sample);
ElectricPotential::new::<millivolt>(mv as f64)
},
Channel1VRef::Disabled(_) => ElectricPotential::new::<volt>(1.5)
}
}
_ => 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!(),
}
}
/// Calibrates the DAC output to match vref of the MAX driver to reduce zero-current offset of the MAX driver output. /// 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. /// The thermostat DAC applies a control voltage signal to the CTLI pin of MAX driver chip to control its output current.
@ -388,12 +398,12 @@ impl Channels {
// Get current passing through TEC // Get current passing through TEC
pub fn get_tec_i(&mut self, channel: usize) -> ElectricCurrent { pub fn get_tec_i(&mut self, channel: usize) -> ElectricCurrent {
(self.read_itec(channel) - self.read_vref(channel)) / ElectricalResistance::new::<ohm>(0.4) (self.adc_read(channel, PinsAdcReadTarget::ITec, 16) - self.adc_read(channel, PinsAdcReadTarget::VREF, 16)) / ElectricalResistance::new::<ohm>(0.4)
} }
// Get voltage across TEC // Get voltage across TEC
pub fn get_tec_v(&mut self, channel: usize) -> ElectricPotential { pub fn get_tec_v(&mut self, channel: usize) -> ElectricPotential {
(self.read_tec_u_meas(channel) - ElectricPotential::new::<volt>(1.5)) * 4.0 (self.adc_read(channel, PinsAdcReadTarget::VTec, 16) - ElectricPotential::new::<volt>(1.5)) * 4.0
} }
fn set_pwm(&mut self, channel: usize, pin: PwmPin, duty: f64) -> f64 { fn set_pwm(&mut self, channel: usize, pin: PwmPin, duty: f64) -> f64 {
@ -446,7 +456,7 @@ impl Channels {
fn report(&mut self, channel: usize) -> Report { fn report(&mut self, channel: usize) -> Report {
let i_set = self.get_i(channel); let i_set = self.get_i(channel);
let i_tec = self.read_itec(channel); let i_tec = self.adc_read(channel, PinsAdcReadTarget::ITec, 16);
let tec_i = self.get_tec_i(channel); let tec_i = self.get_tec_i(channel);
let dac_value = self.get_dac(channel); let dac_value = self.get_dac(channel);
let state = self.channel_state(channel); let state = self.channel_state(channel);
@ -462,7 +472,7 @@ impl Channels {
pid_engaged: state.pid_engaged, pid_engaged: state.pid_engaged,
i_set, i_set,
dac_value, dac_value,
dac_feedback: self.read_dac_feedback(channel), dac_feedback: self.adc_read(channel, PinsAdcReadTarget::DacVfb, 1),
i_tec, i_tec,
tec_i, tec_i,
tec_u_meas: self.get_tec_v(channel), tec_u_meas: self.get_tec_v(channel),