At 09:21 AM 26/2/97 -0500, you wrote:
>I'm doing instrument control, and have been forced to use external PIC's as
>my only reliable time base because of this non-real-time OS that Windows
>is...  Is there a way to suspend the multitasking and get reliable
>execution speed out of windows?  Is this possible from high-level languages
>(like VB?)  Or must one write a device driver/DLL?
>
[snip]

NOP, you can "Enter Critical Section" to prevent task-swithcing
(not direct from VB) but this is not enough.

VxD ( or code running at ring-0 ) is the only way to have exact
timing/critical response under Windows.
Any normal code may be interrupted by some Windows internal tasks.
A CLI (Clear Interrupt) only marks a software flag for a VM machine
it does nothing more.

antti

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