turning inputs into outputs

[Huron Warriors]

I believe that you did not understand us correctly. Our problem is that we only have 8 pwm outputs on the microcontroller. we would like to add 2 more motors to our system and controll them separately using other pins, like the digital/analog inputs - but we cant seem to get the motor working on these correctly. After we turn pin14 on digital inputs into an output pin, the motor randomly jerks, we guess it doesnt recieve enough voltage, but we havent tested that yet, anyways - still looking for a reply.

P.S - yes, we are Huron heights from Newmarket. We guess we are speaking to Alex Mac - hey guys, nice to meet ya here.

[Bongle]

Originally Posted by Huron Warriors

I believe that you did not understand us correctly. Our problem is that we only have 8 pwm outputs on the microcontroller. we would like to add 2 more motors to our system and controll them separately using other pins, like the digital/analog inputs - but we cant seem to get the motor working on these correctly. After we turn pin14 on digital inputs into an output pin, the motor randomly jerks, we guess it doesnt recieve enough voltage, but we havent tested that yet, anyways - still looking for a reply.

Oh, whoops. As you can guess, I read it as "we want to read from the analog inputs, then drive a motor with that value".

After reading innovationfirst's docs, it looks like it could be possible. In the spec sheet, they say that the analog interrupt ports CAN be used as outputs and can drive "open circuits".

I don't know enough about VEX or the PIC hardware to help beyond that. Good luck!

If I was doing the programming, I'd look at the various IFI functions that access the ADC and see if you can find some that might let you set values. The OpenADC function called from ifi_utilities.c looks hopeful.

[Qbranch]

Are you outputting a PWM signal? Or did you just set the tristate to 1?

also you might want to have a look at this post of mine... it might help a little.

if you arent outputting PWM, you'll need to set up a timer or CCP to use as a PWM timebase and another CCP for each individual motor channel.... also you'll need to see what pins on the microcontroller are connected to which pins on the I/O pins...

is this what you need? either way let me know.

-q