... signal5. Supporting optocoupler isolation ERR signal output function and interaction with the upper computer6. Supporting half-current function7. the maximum micro ... , 6.Micro step2, 4, 5, 8, 10, 16, 20, 25, 32, 40, 50, 64, 100, 128, 200, 256Input signalThree control signal ... output, maximum current: 20mAProtectionOver-voltage, under-voltage, short circuit, overheat Stepper motor driver 2M880N