//! This shows using Parallel IO to output 4 bit parallel data at 1MHz clock //! rate. //! //! Uses GPIO 1, 2, 3 and 4 as the data pins. //! GPIO 5 as the "valid pin" (driven high during an active transfer) and GPIO //! 8 as the clock signal output. //! //! You can use a logic analyzer to see how the pins are used. //% CHIPS: esp32c6 esp32h2 //% FEATURES: async embassy embassy-time-timg0 embassy-generic-timers #![no_std] #![no_main] use embassy_executor::Spawner; use embassy_time::{Duration, Timer}; use esp_backtrace as _; use esp_hal::{ clock::ClockControl, dma::{Dma, DmaPriority}, dma_buffers, gpio::Io, parl_io::{ BitPackOrder, ClkOutPin, ParlIoTxOnly, SampleEdge, TxFourBits, TxPinConfigWithValidPin, }, peripherals::Peripherals, prelude::*, system::SystemControl, timer::timg::TimerGroup, }; use esp_println::println; #[main] async fn main(_spawner: Spawner) { esp_println::println!("Init!"); let peripherals = Peripherals::take(); let system = SystemControl::new(peripherals.SYSTEM); let clocks = ClockControl::boot_defaults(system.clock_control).freeze(); let timg0 = TimerGroup::new_async(peripherals.TIMG0, &clocks); esp_hal_embassy::init(&clocks, timg0); let io = Io::new(peripherals.GPIO, peripherals.IO_MUX); let (tx_buffer, mut tx_descriptors, _, mut rx_descriptors) = dma_buffers!(32000, 0); let dma = Dma::new(peripherals.DMA); let dma_channel = dma.channel0; let tx_pins = TxFourBits::new(io.pins.gpio1, io.pins.gpio2, io.pins.gpio3, io.pins.gpio4); let mut pin_conf = TxPinConfigWithValidPin::new(tx_pins, io.pins.gpio5); let parl_io = ParlIoTxOnly::new( peripherals.PARL_IO, dma_channel.configure_for_async( false, &mut tx_descriptors, &mut rx_descriptors, DmaPriority::Priority0, ), 1.MHz(), &clocks, ) .unwrap(); let mut clock_pin = ClkOutPin::new(io.pins.gpio8); let mut parl_io_tx = parl_io .tx .with_config( &mut pin_conf, &mut clock_pin, 0, SampleEdge::Normal, BitPackOrder::Msb, ) .unwrap(); let buffer = tx_buffer; for i in 0..buffer.len() { buffer[i] = (i % 255) as u8; } loop { parl_io_tx.write_dma_async(buffer).await.unwrap(); println!("Transferred {} bytes", buffer.len()); Timer::after(Duration::from_millis(500)).await; } }