embassy/examples/stm32f4/src/bin/usb_serial.rs
2023-11-13 01:56:50 +01:00

128 lines
3.9 KiB
Rust

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use defmt::{panic, *};
use embassy_executor::Spawner;
use embassy_stm32::time::Hertz;
use embassy_stm32::usb_otg::{Driver, Instance};
use embassy_stm32::{bind_interrupts, peripherals, usb_otg, Config};
use embassy_usb::class::cdc_acm::{CdcAcmClass, State};
use embassy_usb::driver::EndpointError;
use embassy_usb::Builder;
use futures::future::join;
use {defmt_rtt as _, panic_probe as _};
bind_interrupts!(struct Irqs {
OTG_FS => usb_otg::InterruptHandler<peripherals::USB_OTG_FS>;
});
#[embassy_executor::main]
async fn main(_spawner: Spawner) {
info!("Hello World!");
let mut config = Config::default();
{
use embassy_stm32::rcc::*;
config.rcc.hse = Some(Hse {
freq: Hertz(8_000_000),
mode: HseMode::Bypass,
});
config.rcc.pll_src = PllSource::HSE;
config.rcc.pll = Some(Pll {
prediv: PllPreDiv::DIV4,
mul: PllMul::MUL168,
divp: Some(PllPDiv::DIV2), // 8mhz / 4 * 168 / 2 = 168Mhz.
divq: Some(PllQDiv::DIV7), // 8mhz / 4 * 168 / 7 = 48Mhz.
divr: None,
});
config.rcc.ahb_pre = AHBPrescaler::DIV1;
config.rcc.apb1_pre = APBPrescaler::DIV4;
config.rcc.apb2_pre = APBPrescaler::DIV2;
config.rcc.sys = Sysclk::PLL1_P;
}
let p = embassy_stm32::init(config);
// Create the driver, from the HAL.
let mut ep_out_buffer = [0u8; 256];
let mut config = embassy_stm32::usb_otg::Config::default();
config.vbus_detection = true;
let driver = Driver::new_fs(p.USB_OTG_FS, Irqs, p.PA12, p.PA11, &mut ep_out_buffer, config);
// Create embassy-usb Config
let mut config = embassy_usb::Config::new(0xc0de, 0xcafe);
config.manufacturer = Some("Embassy");
config.product = Some("USB-serial example");
config.serial_number = Some("12345678");
// 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 [], // no msos descriptors
&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<EndpointError> 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?;
}
}