embassy/examples/stm32g4/src/bin/usb_serial.rs
2023-11-13 00:52:01 +01:00

120 lines
3.4 KiB
Rust

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use defmt::{panic, *};
use embassy_executor::Spawner;
use embassy_stm32::rcc::{Clock48MhzSrc, ClockSrc, Hsi48Config, Pll, PllM, PllN, PllQ, PllR, PllSource};
use embassy_stm32::time::Hertz;
use embassy_stm32::usb::{self, Driver, Instance};
use embassy_stm32::{bind_interrupts, peripherals, 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 {
USB_LP => usb::InterruptHandler<peripherals::USB>;
});
#[embassy_executor::main]
async fn main(_spawner: Spawner) {
let mut config = Config::default();
// Change this to `false` to use the HSE clock source for the USB. This example assumes an 8MHz HSE.
const USE_HSI48: bool = true;
let plldivq = if USE_HSI48 { None } else { Some(PllQ::DIV6) };
config.rcc.pll = Some(Pll {
source: PllSource::HSE(Hertz(8_000_000)),
prediv_m: PllM::DIV2,
mul_n: PllN::MUL72,
div_p: None,
div_q: plldivq,
// Main system clock at 144 MHz
div_r: Some(PllR::DIV2),
});
config.rcc.mux = ClockSrc::PLL;
if USE_HSI48 {
// Sets up the Clock Recovery System (CRS) to use the USB SOF to trim the HSI48 oscillator.
config.rcc.clock_48mhz_src = Some(Clock48MhzSrc::Hsi48(Hsi48Config { sync_from_usb: true }));
} else {
config.rcc.clock_48mhz_src = Some(Clock48MhzSrc::PllQ);
}
let p = embassy_stm32::init(config);
info!("Hello World!");
let driver = Driver::new(p.USB, Irqs, p.PA12, p.PA11);
let mut config = embassy_usb::Config::new(0xc0de, 0xcafe);
config.manufacturer = Some("Embassy");
config.product = Some("USB-Serial Example");
config.serial_number = Some("123456");
config.device_class = 0xEF;
config.device_sub_class = 0x02;
config.device_protocol = 0x01;
config.composite_with_iads = true;
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,
);
let mut class = CdcAcmClass::new(&mut builder, &mut state, 64);
let mut usb = builder.build();
let usb_fut = usb.run();
let echo_fut = async {
loop {
class.wait_connection().await;
info!("Connected");
let _ = echo(&mut class).await;
info!("Disconnected");
}
};
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?;
}
}