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Unread 04-10-2005, 07:52
foobert foobert is offline
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Re: VEX Optical Shaft encoders in FRC

Quote:
Originally Posted by BrianBSL
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.
the motor outputs on the vex controller are re7, rg0, rg3, rg4, re0, re1, re2 and re3 on the user controller. the first four of these are pins that may be used for hardware pwm. just for laughs i used pins 1 and 2 to control the brightness of a couple of leds according to stick positions.

the master controller does indeed appear to do little but decode the signal from the radio. out of every 18.5 ms it spends 6 to 12 ms decoding ppm input from the radio and then has 6 ms in which to push the data over the spi bus to the user controller. and it will do this for two radios.

i think the master also controls the reset on the user controller.
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