embassy/examples/stm32g4/src/bin/adc_oversampling.rs
2024-07-11 10:33:43 +08:00

58 lines
1.8 KiB
Rust

//! adc oversampling example
//!
//! This example uses adc oversampling to achieve 16bit data
#![no_std]
#![no_main]
use defmt::*;
use embassy_executor::Spawner;
use embassy_stm32::adc::vals::{Rovsm, Trovs};
use embassy_stm32::adc::{Adc, SampleTime};
use embassy_stm32::Config;
use embassy_time::Timer;
use {defmt_rtt as _, panic_probe as _};
#[embassy_executor::main]
async fn main(_spawner: Spawner) {
let mut config = Config::default();
{
use embassy_stm32::rcc::*;
config.rcc.pll = Some(Pll {
source: PllSource::HSI,
prediv: PllPreDiv::DIV4,
mul: PllMul::MUL85,
divp: None,
divq: None,
// Main system clock at 170 MHz
divr: Some(PllRDiv::DIV2),
});
config.rcc.mux.adc12sel = mux::Adcsel::SYS;
config.rcc.sys = Sysclk::PLL1_R;
}
let mut p = embassy_stm32::init(config);
let mut adc = Adc::new(p.ADC1);
adc.set_sample_time(SampleTime::CYCLES6_5);
// From https://www.st.com/resource/en/reference_manual/rm0440-stm32g4-series-advanced-armbased-32bit-mcus-stmicroelectronics.pdf
// page652 Oversampler
// Table 172. Maximum output results vs N and M. Grayed values indicates truncation
// 0x00 oversampling ratio X2
// 0x01 oversampling ratio X4
// 0x02 oversampling ratio X8
// 0x03 oversampling ratio X16
// 0x04 oversampling ratio X32
// 0x05 oversampling ratio X64
// 0x06 oversampling ratio X128
// 0x07 oversampling ratio X256
adc.set_oversampling_ratio(0x03); // ratio X3
adc.set_oversampling_shift(0b0000); // no shift
adc.enable_regular_oversampling_mode(Rovsm::RESUMED, Trovs::AUTOMATIC, true);
loop {
let measured = adc.blocking_read(&mut p.PA0);
info!("data: 0x{:X}", measured); //max 0xFFF0 -> 65520
Timer::after_millis(500).await;
}
}