@jamesmunns:beeper.com i am near to make my board work with postcard...just another dumb question, to simulate host side I am using my pc connected via USBSerial to the board and I am using this ultra dumb code to create cobs slice to send, I use the printend data sendig them via terminal reception seems ok but I always fall in deser err of accumulator feed.

this is the dumb code:
```Rust
fn main() {
    
    use postcard::to_slice_cobs;
    let mut buf = [0u8; 32];
    let data: &[u8] = &[0x02, 0x01];
    let used = to_slice_cobs(data, &mut buf).unwrap();
    println!("{:#02X?}",used);

    assert_eq!(used, &[0x04, 0x02, 0x02, 0x01,  0x00]);
}
```

So for example i send 0402020100 as hex from my terminal...what am I doing wrong?