error in speed control mode

I’m using two CANJaguars, but only testing on one for the moment, and when I try to set it to the speed control mode, it doesn’t give speeds anywhere near what I want, and usually throws an error too
>>>>ERROR: status == -1073807298 (0xBFFF003E) in Read() in C:/WindRiver/workspace/BlackJagBridgePlugin/SerialPort.cpp at line 216
I’m using java and have a quadrature encoder attached to a gearbox, which I believe is causing the odd values, but I don’t know why the error is being thrown. Sometimes it works, other times it doesn’t. It seems to have something to do with my PID values (20.0, .1, .01) , but I’m not sure. Any ideas?

Your PID values are way too high. Start with a P of 1 or even 0.1. Set the I to something between 0.1 and 0.01. Set your D value to 0.

A good way of playing “what if?” is using the BDC-Comm program to try different gain values. Apply a light load to output to see if the values are adequate, and use the best values you find in your code.