Hope flows Eternal. The Hope that Windows can run real time !!

Accepted it is not deterministic - but reasonably good accuracy can be achived with,

A. A fast processor on the Motherboard ( > 1Gb) and a RAM of more than 256Mb.
B. A lean installation with all bells and whsitle cut out
C. No application other than your application are running.
D. And have a scan time not below 50mS.

For example I am just producing a sample scantime data that was programmed for a scan time of 50ms. This was on 1.2Gb Pentium 4 machine with a multifunction DAS card capturing 9 channels in software trigger mode. The OS was Win-XP and application software in VB6.

TimeVal		ScanTime(ms)

67599160	-
67599220	60
67599270	50
67599330	60
67599380	50
67599440	60
67599490	50
67599550	60
67599600	50
67599660	60
67599710	50
67599770	60
67599820	50
67599880	60
67599930	50
67599990	60
67600040	50
67600100	60
67600150	50
67600200	50
67600260	60
67600310	50
67600370	60
67600420	50
67600480	60

As can be seen the max deviation is 10ms plus. Not bad for my application as it can do with even 100ms scan -and in which case the consistency was really good. (We however were not able to get anything very consistent below 25ms though )

Raghu