This motor control board is designed to work with the Open Flexure microscope and connect to a Raspberry Pi. It is based around three parallel ATTiny 841 microcontrollers running the Arduino Firmware through SpenceKonde's ATTinyCore.
Each ATTiny 841 controls a ULN2003 Darlington transistor array operating at 5V, running a 28BYJ-48 stepper motor with a 64:1 gear ratio.