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#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use defmt::info;
use embassy_executor::Spawner;
use embassy_nrf::pdm::{self, Config, Pdm};
use embassy_nrf::{bind_interrupts, peripherals};
use embassy_time::Timer;
use fixed::types::I7F1;
use num_integer::Roots;
use {defmt_rtt as _, panic_probe as _};
bind_interrupts!(struct Irqs {
PDM => pdm::InterruptHandler<peripherals::PDM>;
});
#[embassy_executor::main]
async fn main(_p: Spawner) {
let p = embassy_nrf::init(Default::default());
let config = Config::default();
let mut pdm = Pdm::new(p.PDM, Irqs, p.P0_01, p.P0_00, config);
loop {
for gain in [I7F1::from_num(-20), I7F1::from_num(0), I7F1::from_num(20)] {
pdm.set_gain(gain, gain);
info!("Gain = {} dB", defmt::Debug2Format(&gain));
pdm.start().await;
// wait some time till the microphon settled
Timer::after_millis(1000).await;
const SAMPLES: usize = 2048;
let mut buf = [0i16; SAMPLES];
pdm.sample(&mut buf).await.unwrap();
let mean = (buf.iter().map(|v| i32::from(*v)).sum::<i32>() / buf.len() as i32) as i16;
info!(
"{} samples, min {=i16}, max {=i16}, mean {=i16}, AC RMS {=i16}",
buf.len(),
buf.iter().min().unwrap(),
buf.iter().max().unwrap(),
mean,
(buf.iter()
.map(|v| i32::from(*v - mean).pow(2))
.fold(0i32, |a, b| a.saturating_add(b))
/ buf.len() as i32)
.sqrt() as i16,
);
info!("samples: {:?}", &buf);
pdm.stop().await;
Timer::after_millis(100).await;
}
}
}
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