encoder problems......

[Alan Anderson]

Originally Posted by alb4h

Why does hardware plugged into the digital I/O ports effect the motor control?

It shouldn't.

The only thing I can think of is that maybe your Digital Sidecar is having power issues and the PWM signals are losing integrity. Are the BATT and +5v LEDs lit?

[alb4h]

He +5V LED is solid green and the BATT led seems to be lit as well but it quite dim and with a slight pulse (not quite a flash)

[Alan Anderson]

Originally Posted by alb4h

He +5V LED is solid green and the BATT led seems to be lit as well but it quite dim and with a slight pulse (not quite a flash)

That sounds like you don't have 12 volts being supplied to the Digital Sidecar. Can you measure the voltage on its power connector? Make sure you haven't accidentally captured the insulation instead of the conductor in the red and black Wago terminals from the Power Distribution Board.

[alb4h]

You win the prize! The sidecar has a short. The hardware folks will have to replace it tomorrow.

Thanks for your help!
Ann

[msheffels]

Our team found out about shorting the digital sidecar this year too. One of them accidentally shorted the PWM signal for a Victor controller to the +12 V power on the Victor. All of the motors on the robot activated momentarily. Scratch one digital sidecar.

Lessons learned:

1) power down the robot before messing with the wiring.

2) Even though FIRST has done a lot to make the control systems safe, there are still failures that can cause the robot to behave unexpectedly. Always make sure everyone that is anywhere near the robot is paying attention whenever you power it up!

[bob.wolff68]

Wow great diagnosis Alan! :-O