Matt Spencer
496b6bdc71
Key components: - no_std core so it can be used bare metal on embedded systems - default implementation for RPi 2350, with midi input and I2s output using PIO - Visualiser for the web to play with on a dev system
67 lines
1.9 KiB
Rust
67 lines
1.9 KiB
Rust
//! synth-embedded — RP2350 / Embassy audio engine entry point.
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//!
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//! Hardware assumed (adjust pin numbers in spawner calls to match your wiring):
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//! GPIO 9 → I2S BCK (bit clock)
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//! GPIO 10 → I2S LRCK (word select / left-right clock)
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//! GPIO 11 → I2S DATA
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//! GPIO 1 → UART0 RX (MIDI in, 31250 baud)
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//!
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//! Build:
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//! cargo build --release
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//!
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//! Flash (requires probe-rs and a debug probe):
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//! cargo run --release
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#![no_std]
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#![no_main]
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use defmt_rtt as _;
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use panic_probe as _;
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use embassy_executor::Spawner;
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use embassy_rp::{
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bind_interrupts, dma,
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peripherals::{DMA_CH0, DMA_CH1, PIO0, UART0},
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pio::InterruptHandler as PioIrqHandler,
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uart::InterruptHandler as UartIrqHandler,
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};
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use embassy_sync::{blocking_mutex::raw::ThreadModeRawMutex, mutex::Mutex};
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mod audio;
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mod midi;
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mod params;
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use params::SynthParams;
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/// Shared synthesiser state — written by the MIDI task, read by the audio task.
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///
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/// `ThreadModeRawMutex` is appropriate here: both tasks run on core 0 and
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/// the mutex is never accessed from an interrupt handler.
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pub static PARAMS: Mutex<ThreadModeRawMutex, SynthParams> = Mutex::new(SynthParams::new());
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// Register Embassy interrupt handlers for the peripherals we use.
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bind_interrupts!(struct Irqs {
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PIO0_IRQ_0 => PioIrqHandler<PIO0>;
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UART0_IRQ => UartIrqHandler<UART0>;
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DMA_IRQ_0 => dma::InterruptHandler<DMA_CH0>, dma::InterruptHandler<DMA_CH1>;
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});
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#[embassy_executor::main]
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async fn main(spawner: Spawner) {
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let p = embassy_rp::init(Default::default());
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defmt::info!("synth-embedded starting on RP2350");
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// Audio output via PIO0 + DMA (I2S to PCM5102A or compatible DAC).
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spawner.spawn(audio::audio_task(
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p.PIO0,
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p.PIN_9, // BCK
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p.PIN_10, // LRCK
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p.PIN_11, // DATA
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p.DMA_CH0,
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).unwrap());
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// MIDI input via UART0 RX.
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spawner.spawn(midi::midi_task(p.UART0, p.PIN_1, p.DMA_CH1).unwrap());
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}
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