Something to note:
If using a Black Jaguar, the current measurement accuracy below 8A is typically +/-2A. When trying to drive at lower currents, you might be reading 0A when it is actually 2A. Above 8A the current accuracy improves to +/- 1A. (This info is in the
Black Jaguar Datasheet)
The current sense circuit in Black Jaguar is quite accurate in the higher current range. Unfortunately you get the +/- 1A and +/- 2A thing going on in the lower ranges. This is on our list of things that need improvement.
Gray Jaguar is rated at +/- 1A typically. Like Black Jag, it should improve at higher currents.
-David