Motor Adapter for myRIO

Overview

The Motor Adapter for NI myRIO allows you to easily connect and control either one stepper motor, two DC motors or two servos independently through the MXP connector on your myRIO. It has been designed so that no additional circuitry is required to drive motors. The board uses the Allegro A4973, a powerful full-bridge, bidirectional PWM motor controller - just supply power and you're on your way!

Slide switches are used to select which motor configuration (servo or DC / stepper) is used. Servo motors are connected via standard 3-pin headers while DC motors are connected via 6-pin or screw terminal connectors and stepper motors are connected using screw terminals. One quadrature encoder input can be routed between the 6-pin connectors using a DIP switch or wired directly using screw terminals. Filtered motor voltage and current are routed back to the myRIO analog inputs to enable real-time monitoring.

Key Features:

• Uses the myRIO Expansion Port (MXP) connector
• Can be configured to work with 2 DC motors, 1 stepper motor, or 2 RC servos
• Current/voltage sensing and control with high/low gain control and over-current protection
• 6V-16V input voltage using screw-terminal supply connections
• 34-pin female breakout allowing direct user access to signal pins
• Onboard quadature encoder interface to myRIO encoder inputs
• User switches for selecting servo or motor connections
• Power LED indicator

Connector Pin-outs

Motor PWR : DC Motor Power Screw-terminal Block

Servos PWR : Servo Motor Power Screw-terminal Block

Motor 1 and Motor 2 : Digilent standard 6-pin motor/encoder connector (see Digilent Gearmotor)

Using the Adapter with myRIO

Compatibility Notes