The DM542A is a type of two-phase hybrid stepping motor driver for one motor. It is designed for use with 2-phase hybrid stepper motor of all kinds with 42mm to 86mm outside diameter and less than 4.0A phase current.
Input Voltage: 18VDC to 50VDC.
Input Power: <4A up to 80W
Output Current: 1A - 4.2A(peak)
Inputs and Outputs are opto-isolated.
Overvoltage, under voltage, overcorrect, phase short circuit protection
Operating Temperature: -10 to 45 degreesC
15 channel subdivision and automatic idle-current reduction. 8 channels output phase current setting
Replaces the older MD542 Driver

The DM860A is a type of two-phase hybrid stepping motor driver for one motor. The drive voltage is from 24VDC to 80VDC. It is designed for use with 2-phase hybrid stepper motor of all kinds with 57mm to 110mm outside diameter and less than 8.0A phase current.
Inputs and Outputs are opto-isolated.
Overvoltage, under voltage, overcorrect, phase short circuit protection
14 channels subdivision and automatic idle-current reduction. 8 channels output phase current setting
Holding torque when the DM860A is run under high speed is also significantly higher than other two-phase drivers, what’s more, the positioning accuracy is also higher.
It is widely used in middle and big size numerical control devices such as curving machine, CNC machine, and computer embroider machine, packing machines and so on.
Replaces the older MD882 Driver

This stepper motor is the standard for smaller 3d printers such as the RepRap Wallace and Printrbot machines

This stepper motor is used in the new universal mini extruder for repraps.

Board for breaking out the pins on a parallel port cable