Missing data in UART receiver about esp-idf-hal HOT 4 CLOSED

Do you still miss bytes if you busyloop, instead of sleeping? I.e. what happens if you comment out the thread::sleep line?

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Do you still miss bytes if you busyloop, instead of sleeping? I.e. what happens if you comment out the thread::sleep line?

Yes. And watchdog gets triggered

from esp-idf-hal.

i think i got it to work the following way:

let start = SystemTime::now();

const magic_buffer_size_plus_10: usize = 130;
const ticks_to_wait: u32 = 1;

let mut buffer : [u8; magic_buffer_size_plus_10] = [0; magic_buffer_size_plus_10];

while start.elapsed().unwrap().as_secs() < timeout {
  match unsafe { uart_read_bytes(self.port, &mut buffer as *mut u8 as *mut _, magic_buffer_size_plus_10 as u32, ticks_to_wait) } {
    -1 => /* error */,
    val => {
      for i in 0..val {
        data.push(buffer[i as usize]);
      }
    }
  };
}

I am still not 100% sure what is going on exactly but I suspect that current implementation of Read for Rx is inadequate when dealing withe spurs of data sent over a short period of time (600 bytes over just a few milliseconds in my particular case)

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With those kinds of bursts, in general, it is best to use the DMA, or at the very least interrupt-driven. Even when you busy loop the scheduler will swap out the task that your code is running in and you will easily lose data this way. I don't think the DMA has support in Rust just yet, but that may be something you wish to look at.

Thanks for issue! Closing as this doesn't seem to be a bug.

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