Re: 12 and 16-bit oscilloscopes

"Frank Miles" <fpm@xxxxxxxxxxxxxxxx> wrote in message
news:em98kr$l6b$1@xxxxxxxxxxxxxxxxxxxxxxxxxx
Don't you have gaps where the various interrupts take control away?

I imagine Mike disables interrupts if they'd otherwise interrupt what he's
doing.

Windows device drivers can and do disable interrupts and can "hog" the CPU all
they want as well... there's just plenty of admonishments not to do so unless
you really, truly need to, as of course it does tend to make the entire system
sluggish.

Perhaps your application doesn't have this problem, but if the gaps
occur at "critical times" - say, in the middle of a single-shot
acquisition - this would seem to be a problem.

For something like a scope, the data would presumably be buffered in a FIFO
(or similar) anyway, so as long as you can keep up with the average data
coming in, the occasional, brief interrupts shouldn't be a problem.

(That being said... in the server version of Windows OSes on a heavily loaded
machine, *user mode* applications can sometimes be pre-empted for *seconds* at
a time!)

---Joel


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