Problem detecting and reacting to serial break

Daniel O'Connor doconnor at
Mon Aug 16 03:35:41 UTC 2010

On 15/08/2010, at 23:25, Paul Thornton wrote:
> With Linux, it all works as expected - but the linux tcsetattr doesn't
> like the nonstandard baud rate either.  However, in linux I used
> setserial to set a base baud rate of 24000000 and a divisor of 96 to get
> 250k baud rate.  When I run, I have a stable buffer dump displayed which
> always starts with byte 1; so I'm happy that in theory my code is
> correct and the hardware is behaving as expected.

I had a quick look at the uftdi driver and while it has code for setting break (uftdi_cfg_set_break), there doesn't seem to be any in the read call back routine to handle break, hence the TTY layer will not see them.

The Linux driver does (obviously :) support it and it doesn't look too tricky so you could probably fix it up.

It would be nice if the man page mentioned the lack of break support ;(

Daniel O'Connor software and network engineer
for Genesis Software -
"The nice thing about standards is that there
are so many of them to choose from."
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