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Refactoring lockin binaries

This commit is contained in:
Ryan Summers 2021-05-06 13:08:10 +02:00
parent ed34b69823
commit 19b606c385
4 changed files with 69 additions and 163 deletions
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3
.github/workflows/release.yml vendored
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@ -24,8 +24,7 @@ jobs:
- run: >
zip bin.zip
target/*/release/dual-iir
target/*/release/lockin-external
target/*/release/lockin-internal
target/*/release/lockin
- id: create_release
uses: actions/create-release@v1
env:

4
README.md
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@ -29,9 +29,7 @@ to implement different use cases. Several applications are provides by default
* anti-windup
* derivative kick avoidance
### Lockin external
### Lockin internal
### Lockin
## Minimal bootstrapping documentation

143
src/bin/lockin-internal.rs
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@ -1,143 +0,0 @@
#![deny(warnings)]
#![no_std]
#![no_main]
use dsp::{Accu, Complex, ComplexExt, Lockin};
use generic_array::typenum::U2;
use hardware::{Adc1Input, Dac0Output, Dac1Output, AFE0, AFE1};
use stabilizer::{hardware, hardware::design_parameters};
// A constant sinusoid to send on the DAC output.
// Full-scale gives a +/- 10V amplitude waveform. Scale it down to give +/- 1V.
const ONE: i16 = (0.1 * u16::MAX as f32) as _;
const SQRT2: i16 = (ONE as f32 * 0.707) as _;
const DAC_SEQUENCE: [i16; design_parameters::SAMPLE_BUFFER_SIZE] =
[ONE, SQRT2, 0, -SQRT2, -ONE, -SQRT2, 0, SQRT2];
#[rtic::app(device = stm32h7xx_hal::stm32, peripherals = true, monotonic = rtic::cyccnt::CYCCNT)]
const APP: () = {
struct Resources {
afes: (AFE0, AFE1),
adc: Adc1Input,
dacs: (Dac0Output, Dac1Output),
lockin: Lockin<U2>,
}
#[init]
fn init(c: init::Context) -> init::LateResources {
// Configure the microcontroller
let (mut stabilizer, _pounder) = hardware::setup(c.core, c.device);
// Enable ADC/DAC events
stabilizer.adcs.1.start();
stabilizer.dacs.0.start();
stabilizer.dacs.1.start();
// Start sampling ADCs.
stabilizer.adc_dac_timer.start();
init::LateResources {
lockin: Lockin::default(),
afes: stabilizer.afes,
adc: stabilizer.adcs.1,
dacs: stabilizer.dacs,
}
}
/// Main DSP processing routine.
///
/// See `dual-iir` for general notes on processing time and timing.
///
/// This is an implementation of an internal-reference lockin on the ADC1 signal.
/// The reference at f_sample/8 is output on DAC0 and the phase of the demodulated
/// signal on DAC1.
#[task(binds=DMA1_STR4, resources=[adc, dacs, lockin], priority=2)]
fn process(c: process::Context) {
let lockin = c.resources.lockin;
let adc_samples = c.resources.adc.acquire_buffer();
let dac_samples = [
c.resources.dacs.0.acquire_buffer(),
c.resources.dacs.1.acquire_buffer(),
];
// Reference phase and frequency are known.
let pll_phase = 0i32;
let pll_frequency =
1i32 << (32 - design_parameters::SAMPLE_BUFFER_SIZE_LOG2);
// Harmonic index of the LO: -1 to _de_modulate the fundamental (complex conjugate)
let harmonic: i32 = -1;
// Demodulation LO phase offset
let phase_offset: i32 = 1 << 30;
// Log2 lowpass time constant.
let time_constant: u8 = 8;
let sample_frequency = (pll_frequency as i32).wrapping_mul(harmonic);
let sample_phase =
phase_offset.wrapping_add(pll_phase.wrapping_mul(harmonic));
let output: Complex<i32> = adc_samples
.iter()
// Zip in the LO phase.
.zip(Accu::new(sample_phase, sample_frequency))
// Convert to signed, MSB align the ADC sample, update the Lockin (demodulate, filter)
.map(|(&sample, phase)| {
let s = (sample as i16 as i32) << 16;
lockin.update(s, phase, time_constant)
})
// Decimate
.last()
.unwrap()
* 2; // Full scale assuming the 2f component is gone.
// Convert to DAC data.
for (i, data) in DAC_SEQUENCE.iter().enumerate() {
// DAC0 always generates a fixed sinusoidal output.
dac_samples[0][i] = *data as u16 ^ 0x8000;
dac_samples[1][i] = (output.arg() >> 16) as u16 ^ 0x8000;
}
}
#[idle(resources=[afes])]
fn idle(_: idle::Context) -> ! {
loop {
cortex_m::asm::wfi();
}
}
#[task(binds = ETH, priority = 1)]
fn eth(_: eth::Context) {
unsafe { stm32h7xx_hal::ethernet::interrupt_handler() }
}
#[task(binds = SPI2, priority = 3)]
fn spi2(_: spi2::Context) {
panic!("ADC0 input overrun");
}
#[task(binds = SPI3, priority = 3)]
fn spi3(_: spi3::Context) {
panic!("ADC1 input overrun");
}
#[task(binds = SPI4, priority = 3)]
fn spi4(_: spi4::Context) {
panic!("DAC0 output error");
}
#[task(binds = SPI5, priority = 3)]
fn spi5(_: spi5::Context) {
panic!("DAC1 output error");
}
extern "C" {
// hw interrupt handlers for RTIC to use for scheduling tasks
// one per priority
fn DCMI();
fn JPEG();
fn SDMMC();
}
};

60
src/bin/lockin-external.rs → src/bin/lockin.rs
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@ -18,6 +18,13 @@ use stabilizer::hardware::{
use miniconf::Miniconf;
use stabilizer::net::{Action, MqttInterface};
// A constant sinusoid to send on the DAC output.
// Full-scale gives a +/- 10.24V amplitude waveform. Scale it down to give +/- 1V.
const ONE: i16 = ((1.0 / 10.24) * u16::MAX as f32) as _;
const SQRT2: i16 = (ONE as f32 * 0.707) as _;
const DAC_SEQUENCE: [i16; design_parameters::SAMPLE_BUFFER_SIZE] =
[ONE, SQRT2, 0, -SQRT2, -ONE, -SQRT2, 0, SQRT2];
#[derive(Copy, Clone, Debug, Deserialize, Miniconf)]
enum Conf {
PowerPhase,
@ -25,9 +32,16 @@ enum Conf {
Quadrature,
}
#[derive(Copy, Clone, Debug, Miniconf, Deserialize, PartialEq)]
enum LockinMode {
Internal,
External,
}
#[derive(Copy, Clone, Debug, Deserialize, Miniconf)]
pub struct Settings {
afe: [AfeGain; 2],
lockin_mode: LockinMode,
pll_tc: [u8; 2],
@ -36,6 +50,7 @@ pub struct Settings {
lockin_phase: i32,
output_conf: [Conf; 2],
telemetry_period_secs: u16,
}
impl Default for Settings {
@ -43,6 +58,8 @@ impl Default for Settings {
Self {
afe: [AfeGain::G1; 2],
lockin_mode: LockinMode::External,
pll_tc: [21, 21], // frequency and phase settling time (log2 counter cycles)
lockin_tc: 6, // lockin lowpass time constant
@ -50,6 +67,7 @@ impl Default for Settings {
lockin_phase: 0, // Demodulation LO phase offset
output_conf: [Conf::Quadrature; 2],
telemetry_period_secs: 10,
}
}
}
@ -145,21 +163,49 @@ const APP: () = {
let lockin = c.resources.lockin;
let settings = c.resources.settings;
let mut pll_frequency = 0;
let (sample_phase, sample_frequency) = match settings.lockin_mode {
LockinMode::External => {
let timestamp =
c.resources.timestamper.latest_timestamp().unwrap_or(None); // Ignore data from timer capture overflows.
let (pll_phase, pll_frequency) = c.resources.pll.update(
let (pll_phase, frequency) = c.resources.pll.update(
timestamp.map(|t| t as i32),
settings.pll_tc[0],
settings.pll_tc[1],
);
pll_frequency = frequency;
let sample_frequency = ((pll_frequency
>> design_parameters::SAMPLE_BUFFER_SIZE_LOG2)
as i32)
.wrapping_mul(settings.lockin_harmonic);
let sample_phase = settings
.lockin_phase
.wrapping_add(pll_phase.wrapping_mul(settings.lockin_harmonic));
let sample_phase = settings.lockin_phase.wrapping_add(
pll_phase.wrapping_mul(settings.lockin_harmonic),
);
(sample_phase, sample_frequency)
}
LockinMode::Internal => {
// Reference phase and frequency are known.
let pll_phase = 0i32;
let pll_frequency =
1i32 << (32 - design_parameters::SAMPLE_BUFFER_SIZE_LOG2);
// Demodulation LO phase offset
let phase_offset: i32 = 1 << 30;
let sample_frequency = (pll_frequency as i32)
.wrapping_mul(settings.lockin_harmonic);
let sample_phase = phase_offset.wrapping_add(
pll_phase.wrapping_mul(settings.lockin_harmonic),
);
(sample_phase, sample_frequency)
}
};
let output: Complex<i32> = adc_samples[0]
.iter()
@ -190,7 +236,13 @@ const APP: () = {
// Convert to DAC data.
for i in 0..dac_samples[0].len() {
// When operating in internal lockin mode, DAC0 is always used for generating the
// reference signal.
if settings.lockin_mode == LockinMode::Internal {
dac_samples[0][i] = DAC_SEQUENCE[i] as u16 ^ 0x8000;
} else {
dac_samples[0][i] = (output[0] >> 16) as u16 ^ 0x8000;
}
dac_samples[1][i] = (output[1] >> 16) as u16 ^ 0x8000;
}
}