In SX Microcontrollers, SX/B Compiler and SX-Key Tool, camerazn wrote:

I'm trying to control two Victor 883 speed controllers using PWM. The v883s expect pulses between 1 and 3 ms in length (I'm pretty sure), and I'd like to be able to vary the duty cycle between 10% and 100%.

Right now I'm using lightly modified example code posted by JonnyMac found here:
http://forums.parallax.com/forums/default.aspx?f=7&m=258538

The PWM in the code works, but the pulses are too short for the v883 to recognize (about 3/4 ms). I tried changing the clock speed, but that did not change the pulse duration, only the period of time for which the pulses occurred. When I put it in non-Turbo mode, the pulses were too long (about 14 ms in length).

Any ideas how to time 

Furthermore, I on the professional development board, I have rb.0 running to servo channel 0 and rb.1 running to servo channel 1. It appears signal is only coming out of pin rb.0. I verified this with my scope by switching wires around. It's probably a problem with my breadboard (hope not) or something along those lines.

Thanks for any and all help!


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Fake edit:
I'm reading about PULSOUT, and that is probably the solution. However, is there something akin to the PAUSE function which takes its argument in us, not ms?

Pseudocode example:

PWM_Freq = 200 ;; 200us
PWM_ON   = 50   ;; 50us
PWM_OFF  = 200-PWM_ON
;;Begin interrupt
     PULSOUT PWM_ON
     WAIT PWM_OFF
;;end interrupt

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