From a60d92cfbbacc909ba781802cad04fe00e849026 Mon Sep 17 00:00:00 2001 From: Michael van Niekerk Date: Mon, 24 Jul 2023 22:20:00 +0200 Subject: [PATCH] Tx and Rx setup --- examples/rp/.idea/.gitignore | 8 + examples/rp/.idea/modules.xml | 8 + examples/rp/.idea/rp.iml | 12 ++ examples/rp/.idea/vcs.xml | 6 + examples/rp/src/bin/pio_uart.rs | 262 ++++++++++++++++++++++++++++++++ 5 files changed, 296 insertions(+) create mode 100644 examples/rp/.idea/.gitignore create mode 100644 examples/rp/.idea/modules.xml create mode 100644 examples/rp/.idea/rp.iml create mode 100644 examples/rp/.idea/vcs.xml create mode 100644 examples/rp/src/bin/pio_uart.rs diff --git a/examples/rp/.idea/.gitignore b/examples/rp/.idea/.gitignore new file mode 100644 index 000000000..13566b81b --- /dev/null +++ b/examples/rp/.idea/.gitignore @@ -0,0 +1,8 @@ +# Default ignored files +/shelf/ +/workspace.xml +# Editor-based HTTP Client requests +/httpRequests/ +# Datasource local storage ignored files +/dataSources/ +/dataSources.local.xml diff --git a/examples/rp/.idea/modules.xml b/examples/rp/.idea/modules.xml new file mode 100644 index 000000000..06ff4b23d --- /dev/null +++ b/examples/rp/.idea/modules.xml @@ -0,0 +1,8 @@ + + + + + + + + \ No newline at end of file diff --git a/examples/rp/.idea/rp.iml b/examples/rp/.idea/rp.iml new file mode 100644 index 000000000..9b4cf845b --- /dev/null +++ b/examples/rp/.idea/rp.iml @@ -0,0 +1,12 @@ + + + + + + + + + + + + \ No newline at end of file diff --git a/examples/rp/.idea/vcs.xml b/examples/rp/.idea/vcs.xml new file mode 100644 index 000000000..b2bdec2d7 --- /dev/null +++ b/examples/rp/.idea/vcs.xml @@ -0,0 +1,6 @@ + + + + + + \ No newline at end of file diff --git a/examples/rp/src/bin/pio_uart.rs b/examples/rp/src/bin/pio_uart.rs new file mode 100644 index 000000000..14d05f4db --- /dev/null +++ b/examples/rp/src/bin/pio_uart.rs @@ -0,0 +1,262 @@ +//! This example shows how to use USB (Universal Serial Bus) in the RP2040 chip. +//! +//! This creates a USB serial port that echos. + +#![no_std] +#![no_main] +#![feature(type_alias_impl_trait)] + +use defmt::{info, panic}; +use embassy_executor::Spawner; +use embassy_futures::join::join; +use embassy_rp::bind_interrupts; +use embassy_rp::peripherals::{PIO0, USB}; +use embassy_rp::usb::{Driver, Instance, InterruptHandler}; +use embassy_usb::class::cdc_acm::{CdcAcmClass, State}; +use embassy_usb::driver::EndpointError; +use embassy_usb::{Builder, Config}; +use embassy_rp::pio::{InterruptHandler as PioInterruptHandler}; +use {defmt_rtt as _, panic_probe as _}; + +bind_interrupts!(struct UsbIrqs { + USBCTRL_IRQ => InterruptHandler; +}); + +bind_interrupts!(struct PioIrqs { + PIO0_IRQ_0 => PioInterruptHandler; +}); + +#[embassy_executor::main] +async fn main(_spawner: Spawner) { + info!("Hello there!"); + + let p = embassy_rp::init(Default::default()); + + // Create the driver, from the HAL. + let driver = Driver::new(p.USB, UsbIrqs); + + // Create embassy-usb Config + let mut config = Config::new(0xc0de, 0xcafe); + config.manufacturer = Some("Embassy"); + config.product = Some("PIO UART example"); + config.serial_number = Some("12345678"); + config.max_power = 100; + config.max_packet_size_0 = 64; + + // Required for windows compatibility. + // https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.9.1/kconfig/CONFIG_CDC_ACM_IAD.html#help + config.device_class = 0xEF; + config.device_sub_class = 0x02; + config.device_protocol = 0x01; + config.composite_with_iads = true; + + // Create embassy-usb DeviceBuilder using the driver and config. + // It needs some buffers for building the descriptors. + let mut device_descriptor = [0; 256]; + let mut config_descriptor = [0; 256]; + let mut bos_descriptor = [0; 256]; + let mut control_buf = [0; 64]; + + let mut state = State::new(); + + let mut builder = Builder::new( + driver, + config, + &mut device_descriptor, + &mut config_descriptor, + &mut bos_descriptor, + &mut control_buf, + ); + + // Create classes on the builder. + let mut class = CdcAcmClass::new(&mut builder, &mut state, 64); + + // Build the builder. + let mut usb = builder.build(); + + // Run the USB device. + let usb_fut = usb.run(); + + // Do stuff with the class! + let echo_fut = async { + loop { + class.wait_connection().await; + info!("Connected"); + let _ = echo(&mut class).await; + info!("Disconnected"); + } + }; + + // Run everything concurrently. + // If we had made everything `'static` above instead, we could do this using separate tasks instead. + join(usb_fut, echo_fut).await; +} + +struct Disconnected {} + +impl From for Disconnected { + fn from(val: EndpointError) -> Self { + match val { + EndpointError::BufferOverflow => panic!("Buffer overflow"), + EndpointError::Disabled => Disconnected {}, + } + } +} + +async fn echo<'d, T: Instance + 'd>(class: &mut CdcAcmClass<'d, Driver<'d, T>>) -> Result<(), Disconnected> { + let mut buf = [0; 64]; + loop { + let n = class.read_packet(&mut buf).await?; + let data = &buf[..n]; + info!("data: {:x}", data); + class.write_packet(data).await?; + } +} + +mod uart { + use embassy_rp::peripherals::PIO0; + use embassy_rp::pio::{Common, Pio, PioPin, StateMachine}; + use embassy_rp::Peripheral; + + use crate::PioIrqs; + + pub struct PioUart<'a> { + baud: u64, + pio: Common<'a, PIO0>, + sm0: StateMachine<'a, PIO0, 0>, + sm1: StateMachine<'a, PIO0, 1>, + } + + impl<'a> PioUart<'a> { + pub async fn new( + baud: u64, + pio: impl Peripheral

+ 'a, + tx_pin: impl PioPin, + rx_pin: impl PioPin, + ) -> PioUart<'a> { + let Pio { + mut common, + mut sm0, + mut sm1, + .. + } = Pio::new(pio, PioIrqs); + + crate::uart_tx::setup_uart_tx_on_sm0(&mut common, &mut sm0, tx_pin, baud); + crate::uart_rx::setup_uart_rx_on_sm1(&mut common, &mut sm1, rx_pin, baud); + + PioUart { + baud, + pio: common, + sm0, + sm1, + } + } + } +} + +mod uart_tx { + use embassy_rp::gpio::Level; + use embassy_rp::peripherals::PIO0; + use embassy_rp::pio::{Common, Config, Direction, FifoJoin, PioPin, ShiftDirection, StateMachine}; + use embassy_rp::relocate::RelocatedProgram; + use fixed::traits::ToFixed; + use fixed_macro::types::U56F8; + + pub fn setup_uart_tx_on_sm0<'a>( + common: &mut Common<'a, PIO0>, + sm_tx: &mut StateMachine<'a, PIO0, 0>, + tx_pin: impl PioPin, + baud: u64, + ) { + let prg = pio_proc::pio_asm!( + r#" + ;.program uart_tx + .side_set 1 opt + + ; An 8n1 UART transmit program. + ; OUT pin 0 and side-set pin 0 are both mapped to UART TX pin. + + pull side 1 [7] ; Assert stop bit, or stall with line in idle state + set x, 7 side 0 [7] ; Preload bit counter, assert start bit for 8 clocks + bitloop: ; This loop will run 8 times (8n1 UART) + out pins, 1 ; Shift 1 bit from OSR to the first OUT pin + jmp x-- bitloop [6] ; Each loop iteration is 8 cycles. + "# + ); + let tx_pin = common.make_pio_pin(tx_pin); + sm_tx.set_pins(Level::High, &[&tx_pin]); + sm_tx.set_pin_dirs(Direction::Out, &[&tx_pin]); + + let relocated = RelocatedProgram::new(&prg.program); + let mut cfg = Config::default(); + + cfg.use_program(&common.load_program(&relocated), &[&tx_pin]); + cfg.clock_divider = (U56F8!(125_000_000) / (8 * baud)).to_fixed(); + cfg.shift_out.auto_fill = false; + cfg.shift_out.direction = ShiftDirection::Right; + cfg.fifo_join = FifoJoin::TxOnly; + cfg.set_out_pins(&[&tx_pin]); + cfg.set_set_pins(&[&tx_pin]); + sm_tx.set_config(&cfg); + sm_tx.set_enable(true) + } +} + +mod uart_rx { + use embassy_rp::gpio::Level; + use embassy_rp::peripherals::PIO0; + use embassy_rp::pio::{Common, Config, Direction, FifoJoin, PioPin, ShiftDirection, StateMachine}; + use embassy_rp::relocate::RelocatedProgram; + use fixed::traits::ToFixed; + use fixed_macro::types::U56F8; + + pub fn setup_uart_rx_on_sm1<'a>( + common: &mut Common<'a, PIO0>, + sm_rx: &mut StateMachine<'a, PIO0, 1>, + rx_pin: impl PioPin, + baud: u64, + ) { + let prg = pio_proc::pio_asm!( + r#" + ;.program uart_rx + + ; Slightly more fleshed-out 8n1 UART receiver which handles framing errors and + ; break conditions more gracefully. + ; IN pin 0 and JMP pin are both mapped to the GPIO used as UART RX. + + start: + wait 0 pin 0 ; Stall until start bit is asserted + set x, 7 [10] ; Preload bit counter, then delay until halfway through + bitloop: ; the first data bit (12 cycles incl wait, set). + in pins, 1 ; Shift data bit into ISR + jmp x-- bitloop [6] ; Loop 8 times, each loop iteration is 8 cycles + jmp pin good_stop ; Check stop bit (should be high) + + irq 4 rel ; Either a framing error or a break. Set a sticky flag, + wait 1 pin 0 ; and wait for line to return to idle state. + jmp start ; Don't push data if we didn't see good framing. + + good_stop: ; No delay before returning to start; a little slack is + push ; important in case the TX clock is slightly too fast. + "# + ); + + let rx_pin = common.make_pio_pin(rx_pin); + sm_rx.set_pins(Level::High, &[&rx_pin]); + sm_rx.set_pin_dirs(Direction::In, &[&rx_pin]); + + let relocated = RelocatedProgram::new(&prg.program); + let mut cfg = Config::default(); + + cfg.use_program(&common.load_program(&relocated), &[&rx_pin]); + cfg.clock_divider = (U56F8!(125_000_000) / (8 * baud)).to_fixed(); + cfg.shift_out.auto_fill = false; + cfg.shift_out.direction = ShiftDirection::Right; + cfg.fifo_join = FifoJoin::RxOnly; + cfg.set_in_pins(&[&rx_pin]); + cfg.set_jmp_pin(&rx_pin); + // cfg.set_set_pins(&[&rx_pin]); + sm_rx.set_config(&cfg); + sm_rx.set_enable(true) + } +}