"unruh" <[email protected]> wrote in message
news:[email protected]...
[]
If rise time is preserved, the pulse is preserved.
If there are no reflections, but in general, yes.
A 10us pulse will
begin to be wiped out once the rise time gets longer than 10us.
If the rs232 really filters so strongly that a 10us pulse gets lost,
then the timing will never be better than about 10us either. I suspect
that the DCD interrupt signal actually gets treated better than that.
It would be worth checking some schematics and chip specifications.
Carrier detect on a normal analog phone modem would be quite happy to give
an indication within a second of the carrier appearing!
The sure board alreae has a very very bright blue led in sync with the
PPS. Yes, it is nice for confirmation
So bright I've had to hide mine from view!
David
_______________________________________________
questions mailing list
[email protected]
http://lists.ntp.org/listinfo/questions
