--- Quote Start ---
originally posted by tns1@Nov 25 2004, 01:17 AM
the datasheet is contradictory on this point. is the tx_empty bit latched high only once when the empty condition first occurs, or continously as long as the empty condition exists? the paragraph manages to say both things. your fix suggests it is the latter case. if so, the ack following the polling seems to be useless. --- Quote End ---
The datasheet is clear that for a "Real-time" reading of the fifo empty state you must 'clear' the bit FIRST. I hadn't actually spotted the code clearing it after polling it, which does appear to be redundant now. The whole concept of this bit being latched is somewhat bizarre, even in an interrupt-driven system.
I was also surprised to see that network transmission is effectively polled - One task continually sending packets will hog all available CPU time.
- Roddy
Honored Contributor
