RepRap A4988 Stepper Motor Driver Module with Heatsink Stepstick for TEVO Tornado, 2 Pieces

Direct replacement for tevo tornado stepper drivers. Some instructions would be nice but I've done some research and got them up and running. Basically these have digipots on them, so all adjustments need to be made in the firmware. In the advanced configuration file, search for stepper driver configuration and you'll come across settings for all the different motors on your machine. I was adding a driver for a new extruder motor, so I adjusted the E1 max current to 700ma. You must know the max current the motor associated with the driver can handle. Updated firmware and it runs like a dream.

This is exactly the part i need but i don't know how to adjust.