STM32f7 UART cannot be read over virtual COM port (USART2)

[andyblarblar]

Hello, I've been looking at using this libarary for a project but I cannot get UART to work for the life of me. I'm using a nucleo-f767ZI, so I should have a virtual com port on USART2. To test, I modified the stm32f7/usart_dma example to use USART2, rather than 7:

#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]

use core::fmt::Write;

use defmt::*;
use embassy_executor::Spawner;
use embassy_stm32::dma::NoDma;
use embassy_stm32::usart::{Config, Uart};
use heapless::String;
use {defmt_rtt as _, panic_probe as _};

#[embassy_executor::main]
async fn main(_spawner: Spawner) {
    let p = embassy_stm32::init(Default::default());
    let config = Config::default();
    let mut usart = Uart::new(p.USART2, p.PA3, p.PA2, p.DMA1_CH6, p.DMA1_CH5, config);

    for n in 0u32.. {
        let mut s: String<128> = String::new();
        core::write!(&mut s, "Hello DMA World {}!\r\n", n).unwrap();

        unwrap!(usart.write(s.as_bytes()).await);

        info!("wrote DMA");
    }
}

When connecting to this port on linux /dev/ttyACM0, I get a connection message, but no data when connecting from TIO, miniterm, or rust itself, all at baud 115200.

I'm quite stumpted with this one, so any help would be appricated. Thanks!

[Dirbaio]

according to the manual section 6.9, it's USART3 on PD8/PD9

[andyblarblar]

according to the manual section 6.9, it's USART3 on PD8/PD9

Ah, well that's embarrassing. Thanks for the manual, it works perfectly fine on USART3.