DIO vs PPM Can NI RoboReo read PPM?

[Ron Nielsen]

I think I understand the difference between PWM signals and PPM signals, how are PPM signals different from DIO? Is PPM a sub type of DIO? Can the NI RoboReo read PPM signals?

[BitTwiddler]

Originally Posted by Ron Nielsen

I think I understand the difference between PWM signals and PPM signals, how are PPM signals different from DIO? Is PPM a sub type of DIO? Can the NI RoboReo read PPM signals?

Pulse Width Modulation (PWM) is not the same thing as Pulse Position Modulation. As the names imply, PWM varies the width of the pulse to effect a change in a motor. PPM varies the position of a pulse within a periodic frame. Both are examples of digital signals but Digital Input/Output (DIO) is a general form of digital interfaces. The PWM and PPM type signals require internal processing of the DIO signals. This is what the Field Programmable Gate Array (FPGA) does for a living.
As far as I know, PPM is not programmed into the RoboRIO's FPGA.

[dellagd]

Originally Posted by Ron Nielsen

I think I understand the difference between PWM signals and PPM signals, how are PPM signals different from DIO? Is PPM a sub type of DIO? Can the NI RoboReo read PPM signals?

Well, yes, but it isn't going to be easy. Since a PPM signal is just pulses, and the RIO can time pulse lengths and position and such, then there's no reason that it couldn't read and decode a PPM signal, but yeah, you'd have to do it manually.

If you decide to write a class to handle a PPM signal, be sure to share it!