Talon SRX QuadEncoder PID Loop

[Ether]

Pardon me if the following questions seem obvious but it's best not to assume.

Originally Posted by E Dawg

At this point we've wired up a quad encoder to the analog breakout

It sounds like you're saying you ran the quadrature outputs of the encoder through an analog breakout... that's not what you meant is it?

Are you wiring the encoder outputs to the SRX or to the roboRIO?

What is the model number of the encoder you are using.

we're not sure where the PID loop is getting error from

The PID in the Talon uses the speed (or position) command it receives via CAN bus from your software as the setpoint for the PID, and uses the signal from the encoder (which must be attached directly to the SRX and not to the roboRIO) as the process variable for the PID. The error is computed by the PID in the SRX by (I assume) subtracting the process variable from the setpoint.

or how to write that to the SRX from the encoder.

As explained above, you don't write the error to the SRX. Your software (in the roboRIO) writes the desired speed (or position) via CAN bus to the SRX.