If you look at PHK's code in FreeBSD this is what is done. The PPS signal > gates the timer, so no interrupt is involved in the time stamp precision. > But yes, it would be interesting to do something on a FPGA. Unfortunately I > wouldn't be able to get to anything like that myself in this lifetime. >
Does the hardware on the NET4501 allow this? Standard PC hardware doesn't. I thought the 4501 used a "Pentium" CPU and the counter would be internal to the CPU and you'd have to read out the count in an interrupt handler. I have read the Linux code for this, which I hear is about the same as BSD. But then I read the common x86 achitecture. -- Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
