Subject: RE: Lowest serial latency?
To: None <>
From: Martin Husemann <>
List: netbsd-users
Date: 12/29/1999 09:39:39
> One thing to do if your milliseconds count is to make sure that
> FIFO_TRIGGER_14 (see /sys/dev/ic/com.c) isn't set on the port.  Either
> by munging (s/TRIGGER_14/TRIGGER_1/), or by placing a 8250/16450-based
> serial card in the machine.

But he was talking about PPS signal, which is usualy delivered via a pulse
on DTR or CD (can't remember), not as normal data. Only the clock data will
be delivered via the serial stream. Does the com driver poll it's ports on
any interrupt? Then trigger level should not matter in this application (but
I haven't looked at the source).