Measuring motor speed

[pfreivald]

Another issue, if you'd indulge...

We have a variable representing our rate, that we want to plug into the PID constructor(?), but we don't know how to change the variable into a PIDSource.

The documentation we were able to find said that you should be able to make any sensor a PIDSource, but we can't find *how*. Here's a screen shot of the code and the errors.

Any help would be most appreciated!