In message <[EMAIL PROTECTED]>, Warner Losh writes:
>If you have only 1 source, then you can use the ack line of the
>parallel port and the ppi driver to get timestamped events. If you
>have more than one, then you might be able to wire a simple latch to
>the ACK line and sample of to 8 sources. That's trickier as their's
>some hair in converting the signals to pulses, worrying about races,
>etc. 1 source gives you nanosecond resolution (but only ms accuracy
>due to interrupt latencies, us if you hack it to be a fast interrupt).
Use the pps driver and you get microsecond jitter with nanosecond
resolution.
The pps driver implements the RFC2783 PPS-API for timestamping
external events.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
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