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Unread 16-12-2003, 09:47
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Re: EDU Interrupt and Timer Template Code

Quote:
Originally Posted by Larry Barello
I admit I was being a bit agressive: I have a 1000 count wheel on a servo motor as my test. I estimated around 1200-1800 RPM which gives 80-120K interrupts a second.

Even with the fix, that interrupt rate crashes the EDU system. It seems that 10-20k/sec is about as fast as it can go. Which is good since a 2 segment wheel on the back of a Boch motor generates about 5k/sec at full speed.
100k interrupts a second is extremely fast for a 40mhz processor. That's only 400 cycles between interrupts. Considering the time to save registers, as well as the fact that IFI has higher priority interupts, I can easily see why you had problems.