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Unread 29-01-2004, 00:00
Larry Barello Larry Barello is offline
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Re: PID control loop/Encoder question

Quote:
Originally Posted by Rickertsen2
Be careful. Even with the new controller, you may run into processor speed limitations if you try to use encoders with a resolution that is too high.
The 2004 controller seems capable of handling at least 5000 counts/sec with two encoders. I am using PORTB interrupt lines (change of state interrupt) and two four stripe encoders (home made) on the shaft of the Bosch. At ~20krpm the encoders give about 5000 counts/sec.

I did some experiments with a super fine resolution encoder and at about 100k counts/sec the IFI system locked up

Anyway, 5k/sec is about right. It gives ~150 counts/26ms loop at top speed.