Click to See Complete Forum and Search --> : Alternate NT PC System Clock Source


Russ Swatek
May 22nd, 1999, 12:23 AM
Just Daydreaming,

This is really a NT Systems question, but this newbie did not find the really appropriate Forum. Please redirect me if a better forum exists. Anyway, all our other development is in VC++ ;-)

My project has a timing requirement to timestamp and initiate events at a 5 millisecond (ms) resolution or better. We also have a Datum bc635PCI Time & Frequency Processor (IRIG-B) board in each of our PCs.

After NT boot and the Datum board initialized to synch with IRIG timecode and generate periodic interrupts at a 5 ms interval, is it feasible to think about disabling the standard PC clock and having the Datum interrupt invoke the NT clock interrupt service routine (ISR) (or some other level such as associated DPC)? Obviously the NT ISR would need to be told that only 5 ms has elapsed rather than whatever the PC standard clock interval is (is there a PC "standard" and does anybody know what it is?).

This approach, if feasible, would have the benefit of making all NT based time services available for use, with just a small wrapper to add an offset time for simulations, ...

Has anybody done this, or know if its feasible, or have any good leads, or ... ?

Thanks,

Russ Swatek
134-F Ralik Rd Box 774
APO AP 96555
swatekr@kmr.ll.mit.edu