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#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
// required-features: dac-adc-pin
#[path = "../common.rs"]
mod common;
use common::*;
use defmt::assert;
use embassy_executor::Spawner;
use embassy_stm32::adc::Adc;
use embassy_stm32::dac::{DacCh1, DacChannel, Value};
use embassy_stm32::dma::NoDma;
use embassy_time::{Delay, Timer};
use {defmt_rtt as _, panic_probe as _};
#[embassy_executor::main]
async fn main(_spawner: Spawner) {
// Initialize the board and obtain a Peripherals instance
let p: embassy_stm32::Peripherals = embassy_stm32::init(config());
#[cfg(feature = "stm32f429zi")]
let dac_peripheral = p.DAC;
#[cfg(any(feature = "stm32h755zi", feature = "stm32g071rb"))]
let dac_peripheral = p.DAC1;
let mut dac: DacCh1<'_, _, NoDma> = DacCh1::new(dac_peripheral, NoDma, p.PA4);
unwrap!(dac.set_trigger_enable(false));
let mut adc = Adc::new(p.ADC1, &mut Delay);
#[cfg(feature = "stm32h755zi")]
let normalization_factor = 256;
#[cfg(any(feature = "stm32f429zi", feature = "stm32g071rb"))]
let normalization_factor: i32 = 16;
unwrap!(dac.set(Value::Bit8(0)));
// Now wait a little to obtain a stable value
Timer::after_millis(30).await;
let offset = adc.read(&mut unsafe { embassy_stm32::Peripherals::steal() }.PA4);
for v in 0..=255 {
// First set the DAC output value
let dac_output_val = to_sine_wave(v);
unwrap!(dac.set(Value::Bit8(dac_output_val)));
// Now wait a little to obtain a stable value
Timer::after_millis(30).await;
// Need to steal the peripherals here because PA4 is obviously in use already
let measured = adc.read(&mut unsafe { embassy_stm32::Peripherals::steal() }.PA4);
// Calibrate and normalize the measurement to get close to the dac_output_val
let measured_normalized = ((measured as i32 - offset as i32) / normalization_factor) as i16;
//info!("value / measured: {} / {}", dac_output_val, measured_normalized);
// The deviations are quite enormous but that does not matter since this is only a quick test
assert!((dac_output_val as i16 - measured_normalized).abs() < 15);
}
info!("Test OK");
cortex_m::asm::bkpt();
}
use core::f32::consts::PI;
use micromath::F32Ext;
fn to_sine_wave(v: u8) -> u8 {
if v >= 128 {
// top half
let r = PI * ((v - 128) as f32 / 128.0);
(r.sin() * 128.0 + 127.0) as u8
} else {
// bottom half
let r = PI + PI * (v as f32 / 128.0);
(r.sin() * 128.0 + 127.0) as u8
}
}
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