I have just assembled by Arduino Mega256/RAMPS 1.6 sandwich, installed the drivers and tried to set the current limiting… but I just get the full supply voltage (24V) on the Vref via (with respect to the -ve supply). I get the same on all four drivers installed.
BTW My steppers are not connected but are MoTech MT-1702HS133A motors that have a 1.33A/phase current limit… so I was looking for about 0.66V on Vref.
BTW2 The RAMPS D1 diode has been removed to stop it backfeeding 24V into the Arduino.
Should I be testing the Vref with just the 5V supply?