esp-hal/examples/src/bin/embassy_i2s_read.rs

//! This shows how to continuously receive data via I2S.
//!
//! Without an additional I2S source device you can connect 3V3 or GND to DIN
//! to read 0 or 0xFF or connect DIN to WS to read two different values.
//!
//! You can also inspect the MCLK, BCLK and WS with a logic analyzer.
//!
//! The following wiring is assumed:
//! - MCLK =>  GPIO0 (not supported on ESP32)
//! - BCLK =>  GPIO2
//! - WS   =>  GPIO4
//! - DIN  =>  GPIO5

//% CHIPS: esp32 esp32c3 esp32c6 esp32h2 esp32s2 esp32s3
//% FEATURES: embassy embassy-generic-timers

#![no_std]
#![no_main]

use embassy_executor::Spawner;
use esp_backtrace as _;
use esp_hal::{
    dma::{Dma, DmaPriority},
    dma_buffers,
    gpio::Io,
    i2s::{asynch::*, DataFormat, I2s, Standard},
    prelude::*,
    timer::timg::TimerGroup,
};
use esp_println::println;

#[esp_hal_embassy::main]
async fn main(_spawner: Spawner) {
    println!("Init!");
    let peripherals = esp_hal::init(esp_hal::Config::default());

    let timg0 = TimerGroup::new(peripherals.TIMG0);
    esp_hal_embassy::init(timg0.timer0);

    let io = Io::new(peripherals.GPIO, peripherals.IO_MUX);

    let dma = Dma::new(peripherals.DMA);
    #[cfg(any(feature = "esp32", feature = "esp32s2"))]
    let dma_channel = dma.i2s0channel;
    #[cfg(not(any(feature = "esp32", feature = "esp32s2")))]
    let dma_channel = dma.channel0;

    let (_, tx_descriptors, rx_buffer, rx_descriptors) = dma_buffers!(0, 4092 * 4);

    let i2s = I2s::new(
        peripherals.I2S0,
        Standard::Philips,
        DataFormat::Data16Channel16,
        44100u32.Hz(),
        dma_channel.configure_for_async(false, DmaPriority::Priority0),
        tx_descriptors,
        rx_descriptors,
    );

    #[cfg(not(feature = "esp32"))]
    let i2s = i2s.with_mclk(io.pins.gpio0);

    let i2s_rx = i2s
        .i2s_rx
        .with_bclk(io.pins.gpio2)
        .with_ws(io.pins.gpio4)
        .with_din(io.pins.gpio5)
        .build();

    let buffer = rx_buffer;
    println!("Start");

    let mut data = [0u8; 5000];
    let mut transaction = i2s_rx.read_dma_circular_async(buffer).unwrap();
    loop {
        let avail = transaction.available().await.unwrap();
        println!("available {}", avail);

        let count = transaction.pop(&mut data).await.unwrap();
        println!(
            "got {} bytes, {:x?}..{:x?}",
            count,
            &data[..10],
            &data[count - 10..count]
        );
    }
}