I need to remotely control a stepper motor with a PPM output. Not to be confused with PWM. That seems very common on here. The motor rotates a specific amount based upon the number of pulses received. Pulse width, to a degree, is not relevant. My problem is I haven't found a transmitter capable of producing pulses fast enough. The motor will buffer pulses sent too fast (up to 500khz), so being too fast is not a real problem. The max rate the motor will accept is 500Khz, the minimum is 220Hz. I need to be above 1khz to have satisfactory control of the motor without adversely affecting my Arduino control program. My first attempt was with Xbee pro s2 using digital IO line passing. The best I could get out of that was about was 20ms pulse train, so 50Hz. As I was trying to figure out why it was so slow I found the hidden spec saying the Xbee was only reliable down to 20ms for line passing. I don't remember if that was reliable or not, but it doesn't matter because that is much slower than I need, so I ditched that Xbee. Next I moved on to Xbee Pro 900HP. It shows to be capable of a 1ms sample rate. Hey! That's 1khz.... that should do it! After decifering the API code to send digital line passing over the Xbee, I found that it was extremely slow and very inconsistent. I had to slow my pulse inputs down to 500ms to get somewhat reliable outputs from the Xbee.
I have 2 questions:
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Has anyone had any success with digital IO line passing using API with transition rates greater than 1khz?
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What about the Yun wifi? Any chance it can be used to create transitions at greater than 1khz on a receiving Yun? I don't have time to set-up and debug this just to find out it can't transfer data that fast.