embassy/examples/stm32h7/src/bin/dac.rs

70 lines
1.9 KiB
Rust

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use cortex_m_rt::entry;
use defmt::*;
use embassy_stm32::dac::{DacCh1, Value};
use embassy_stm32::dma::NoDma;
use embassy_stm32::Config;
use {defmt_rtt as _, panic_probe as _};
#[entry]
fn main() -> ! {
info!("Hello World, dude!");
let mut config = Config::default();
{
use embassy_stm32::rcc::*;
config.rcc.hsi = Some(HSIPrescaler::DIV1);
config.rcc.csi = true;
config.rcc.pll1 = Some(Pll {
source: PllSource::HSI,
prediv: PllPreDiv::DIV4,
mul: PllMul::MUL50,
divp: Some(PllDiv::DIV2),
divq: Some(PllDiv::DIV8), // 100mhz
divr: None,
});
config.rcc.pll2 = Some(Pll {
source: PllSource::HSI,
prediv: PllPreDiv::DIV4,
mul: PllMul::MUL50,
divp: Some(PllDiv::DIV8), // 100mhz
divq: None,
divr: None,
});
config.rcc.sys = Sysclk::PLL1_P; // 400 Mhz
config.rcc.ahb_pre = AHBPrescaler::DIV2; // 200 Mhz
config.rcc.apb1_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.apb2_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.apb3_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.apb4_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.voltage_scale = VoltageScale::Scale1;
config.rcc.adc_clock_source = AdcClockSource::PLL2_P;
}
let p = embassy_stm32::init(config);
let mut dac = DacCh1::new(p.DAC1, NoDma, p.PA4);
loop {
for v in 0..=255 {
dac.set(Value::Bit8(to_sine_wave(v)));
}
}
}
use micromath::F32Ext;
fn to_sine_wave(v: u8) -> u8 {
if v >= 128 {
// top half
let r = 3.14 * ((v - 128) as f32 / 128.0);
(r.sin() * 128.0 + 127.0) as u8
} else {
// bottom half
let r = 3.14 + 3.14 * (v as f32 / 128.0);
(r.sin() * 128.0 + 127.0) as u8
}
}