tree d9662177b2c81a1b341b587b344dcfefb01ff9ed
parent 077258163f0fa53840d3cf155672373cf2d22a2d
author Kévin Redon <kredon@sysmocom.de> 1551970347 +0100
committer Kévin Redon <kredon@sysmocom.de> 1555601240 +0200

switch UART_debug to ASYNC

using the synchronous HAL library causes RX overflow after 5 bytes
on bulk incoming data (e.g. pasted).
this mainly due to printing synchronously the character, but to
further prevent congestion we switch to asynchronous (e.g.
interrupt driven) communication.

The RX part works great now (no overflow), but the TX part is
malfunctioning because the HAL Async library does not buffer the
data to be transmitted and expects it to be in memory until
the transmission is complete (which printf does not do).

This change will not be reflected in Atmel START since it does not
allow to set the underlying STDIO redirect peripheral to async.

Change-Id: If18883e96f336aa9f6b11607859260da5e1503c7