When echoing chatacters on the main UART, some characters are replicated for some reason. Usually the character sent 3/4 chars ago. Tried without the scheduler running, same issue. Tried without the FIFO (similar to the code provided in the reference manual), it's even worse. Tried not echoing, just pissing '0', half the received characters are bad. I noticed the TI bit goes up just after the last bit is transmitted (according to the doc), this might be a timing issue. Tried to delay the sending of the character. Still no luck.