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Unread 03-25-2016, 12:16 AM
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Digital Servo Holding position after disable

I'm hoping there's some RC experts here on CD, because my google-fu is lacking at the moment.

We're using a Hitec digital servo to angle our lift mechanism, on account of the looser servo rules and excellent holding torque and small deadband. My problem is that even if I turn the servo "off" it keeps holding position, unlike an analog servo. This was rather unexpected and a problem, because I want the angle to freewheel while we're lifting, lest I break or fry something. Google tells me this is an unavoidable thing with a digital hitec. So 3 questions for CD:

1. Do digital Futabas work this way? Are there any digital servos that freewheel on loss of signal?
2. Is there a way to programmatically kill power to the PWM outputs?
3. Does anyone know of a way I can abuse WPILib to get a non-PWM signal out of a RoboRIO PWM port? Then I might be able pull a reset signal out of the servo programmer and figure out how to send it to the servo.

Yes, I'll be buying an adequate analog servo in case you guys can't solve my problem, but I'm kinda hoping you can.
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