unruh wrote: [snip]
time that the serial port ioctl returned. I know on my parallel port interrupt, the test I ran showed that the time between activating the pin on the parallel port and the parallel port interrupt service routine timestamping the interrupt was of the order of 1usec. It would be nice to see what it is for the serial port. I doubt it is much more than that.
You might be wrong, and this is supposedly the reason phk started using the parallel port in the first place:
At least some serial ports will gate their interrupt signal to the resolution of their internal clock frequency or hw polling interval, which can result in multiple us's of delay.
OTOH, I have personally never seen this on any of my S1 servers which all use the serial port.
Terje -- - <Terje.Mathisen at tmsw.no> "almost all programming can be viewed as an exercise in caching" _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
