Thread: VEX Optical Shaft encoders in FRC
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Unread 03-10-2005, 10:17
BrianBSL BrianBSL is offline
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Re: VEX Optical Shaft encoders in FRC
Quote:
Originally Posted by foobert
the guys at vexlabs.com discourage the use of interrupts because pwm generation for the motors is done in timing loops, so interrupt processing would cause glitches in the pwm. also, the high priority interrupt is used by timer0 to sync the pwm generation so that it does not happen while r/c data is being sent from the master processor, so that spi interrupts, (also high priority), do not cause glitches in the pwm.

so although they frown on use of the low priority interrupt, they really, really discourage use of the high priority interrupts.
I'm confused by this - on the FRC controller, the PWM outputs are sent by the master uP. Is this not true on the Vex controller? Seems like a waste of a chip then to just do the radio stuff.
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