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