PoolSerial Test

main.rs

//! CDC-ACM serial port example using polling in a busy loop.
#![no_std]
#![no_main]

use core::panic::PanicInfo;
use core::sync::atomic::{self, Ordering};

use cortex_m::asm::delay;
use cortex_m_rt::entry;
use embedded_hal::digital::v2::OutputPin;
use stm32f1xx_hal::usb::{Peripheral, UsbBus};
use stm32f1xx_hal::{pac, prelude::*};
use usb_device::prelude::*;
use usbd_serial::{
    heapless::{pool, Pool},
    typenum::consts::*,
    PoolNode, PoolPort, USB_CLASS_CDC,
};

const NR_NODES: usize = 10;
const POOL_MEM: usize = core::mem::size_of::<PoolNode>() * NR_NODES;

pool!(
    #[allow(non_upper_case_globals)]
    SerialPool: PoolNode
);

#[entry]
fn main() -> ! {
    static mut MEMORY: [u8; POOL_MEM] = [0; POOL_MEM];
    let dp = pac::Peripherals::take().unwrap();

    let mut flash = dp.FLASH.constrain();
    let mut rcc = dp.RCC.constrain();

    let clocks = rcc
        .cfgr
        .use_hse(8.mhz())
        .sysclk(48.mhz())
        .pclk1(24.mhz())
        .freeze(&mut flash.acr);

    assert!(clocks.usbclk_valid());

    // Configure the on-board LED (PC13, green)
    let mut gpioc = dp.GPIOC.split(&mut rcc.apb2);
    let mut _led = gpioc.pc13.into_push_pull_output(&mut gpioc.crh);

    let mut gpioa = dp.GPIOA.split(&mut rcc.apb2);

    // BluePill board has a pull-up resistor on the D+ line.
    // Pull the D+ pin down to send a RESET condition to the USB bus.
    // This forced reset is needed only for development, without it host
    // will not reset your device when you upload new firmware.
    let mut usb_dp = gpioa.pa12.into_push_pull_output(&mut gpioa.crh);
    usb_dp.set_low().ok();
    delay(clocks.sysclk().0 / 100);

    let usb = Peripheral {
        usb: dp.USB,
        pin_dm: gpioa.pa11,
        pin_dp: usb_dp.into_floating_input(&mut gpioa.crh),
    };
    let usb_bus = UsbBus::new(usb);

    SerialPool::grow(MEMORY);
    let wb = SerialPool::alloc().unwrap().init(PoolNode::new());
    let rb = SerialPool::alloc().unwrap().init(PoolNode::new());

    let mut serial = PoolPort::new(&usb_bus, Some(wb), Some(rb)).unwrap();

    let mut usb_dev = UsbDeviceBuilder::new(&usb_bus, UsbVidPid(0x16c0, 0x27dd))
        .manufacturer("Fake company")
        .product("Serial port")
        .serial_number("TEST")
        .device_class(USB_CLASS_CDC)
        .build();

    loop {
        if !usb_dev.poll(&mut [&mut serial]) {
            continue;
        }

        match serial.process() {
            Ok(c) if c > 0 => {
                let rb = serial.replace_reader(None).unwrap();
                serial.replace_writer(Some(rb));
                serial.flush().ok();
            }
            _ => {}
        }
    }
}

#[inline(never)]
#[panic_handler]
fn panic(_info: &PanicInfo) -> ! {
    let gpioc = unsafe { &*pac::GPIOC::ptr() };
    gpioc.bsrr.write(|w| w.bs13().set_bit());
    loop {
        atomic::compiler_fence(Ordering::SeqCst);
    }
}