CNC Shield Expansion Board A4988 Driver for Arduino 3D Printer

This expansion board as a driver expansion board, can be used for engraving machines, 3D printers
It is a total of four slots, can drive four A4988 stepper motor. Each road stepper motors only need two IO ports. In other words, six IO ports can be well managed

Features:
The correspondence between Arduino UNO  and this module IO port

Note:
When inserting the A4988 module, must be careful not to insert opposite. Stepper motor wiring as follows:2A, 2B is a group (red, green), 1A, 1B is a group (blue, yellow), if want to change direction, can be change the position of one group , for example 2A, 2B mutually exchanged