Using VEX Servos

We finally hooked up some servos to PWM01 and PWM02 on our 2006 FRC to start programming. They ran fine with the default code and tank-drive joysticks.

However, shortly after (maybe 2-5 seconds) entering program mode by holding the Prog button, and before activating the IFI Loader (actually the EasyC loader), the servos spazzed out running various directions before coming to rest again.

This occurred at least 3 times last night in our testing which was every time we entered programming mode on the FRC. Lucky for us, our little robot was up on blocks (think safety) so it didn’t run off the table.

Is this a bug in the 2006 master code or a bust in our controller? I hope to re-verify this behavior tonight, but wanted to get this question posted before the weekend support outage.

The customer was using Vex Servos with the FRC. The Vex Servos were designed to work with the Vex Controller and they must always have a constant PWM control signal. If you use Vex Servos with a FRC unit, you may see unwanted behavior whiled disabled or programming. This unwanted behavior is because there is no control signal to the PWM Outputs on the FRC during these 2 states.