To clear the FIFO contents, the
following sequence must be used::
- Write ‘1’ to the CLR control bit
(TXCLR/ RXCLR).
- Wait for clear to complete, i.e.
CLR status bit reflects ‘1’; poll/check for CLR status bit to reflect ‘1’
- Write ‘0’ to CLR control bit
(TXCLR/ RXCLR).
Note: When a
FIFO clear has been initiated, do not try to re-clear it again.
Note: Randomly
changing the FIFO levels when the FIFO has contents might lead to undesired
behavior. It is recommended that the FIFO is cleared before changing the FIFO
thresholds.