PWMing a Victor SP

VEX V5 Technical Support
1

Hi guys - trying to get my Victor SP controlling my motor and I’m having some problems. I haven’t used Victors since the old days of the 884 where you applied a duty cycle between 0 and 100 and got a proportional speed out of your motor. So I wire 12 volts up to my Talon SP and it comes on with the status LEDs blinking orange. I look online that this means it’s not getting a proper PWM signal. I’m not sure why. I have a Tiva launchpad microcomputer outputting a PWM signal at 20hz frequency / 50ms period. The duty cycle is 70%. I’ve double checked this signal using my Saleae logic analyzer so I know it’s right. I’ve hooked the PWM line up to the White line and the ground of my microcomputer up to the Black line. But my status LEDs continue to blink orange.

Couple questions:
-Right now my microcomputer is being powered by my computer. Do I need to hook the microcomputer’s ground to the ground of my Victor? I already have, and it hasn’t made a difference…
-The PWM signal from my tiva is 3.3V peak to peak. Does it need to be 5V peak to peak to be interpreted by the Victor SP? I looked everywhere for an answer on what the peak to peak voltage needed to be and couldn’t find anything. There’s no proper data sheet for the Victor I could find, just short user guides.

Thanks.

2

Probaby better to ask on chief delphi, not many people here have ever seen a Victor SP let alone got it to run a motor

3

Will do. I kinda assumed since Vex make them and this was the Vex forum but…yea, should probably go to the FRC source.

4

Zero,

We’re sorry to hear you’re having difficulty with the Victor SP. To better answer your questions, please email [email protected] with a description of what you are trying to do and what problems you are encountering.

5

The PWM signal should be 1.5ms when off and 1.0/2.0ms for full fwd and rev. This should repeat every 20ms.