serial help ?
alfred at freebsd.org
Thu Apr 19 21:39:30 UTC 2007
I'm working on some custom hardware and I'm getting garbled console
I noticed that siocntxwait looks like this:
* Wait for any pending transmission to finish. Required to avoid
* the UART lockup bug when the speed is changed, and for normal
timo = 100000;
while ((inb(iobase + com_lsr) & (LSR_TSRE | LSR_TXRDY))
!= (LSR_TSRE | LSR_TXRDY) && --timo != 0)
Shouldn't there be some sort of DELAY in there?
My platform has an emulated serial device in hardware, so it
may be that the loop could run a LOT faster than transmit can
any ideas of what the DELAY should be?
- Alfred Perlstein
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