OpenRB-150 Reset with Power On

Technical Support
1

Issue:

I am building a robot with OpenRB-150 as its controller, and I use DC motors and A4990 as their driver. Every time I try to power on the robot, the motor will move in an uncontrolled way, and I need to disconnect and reconnect every time power is switched from off to on, which is very time-consuming. Are all digital pins of OpenRB-150 reset to high when power is turning on? How can I change this?

Besides, every time it’s powered on, there is a chance that the DYNAMIXEL led is off, and the user led blinks. Everything is down unless the reset button is pressed. How can I fix this as well?

2

This post is hard to answer properly as you are not using Robotis actuators but some other unknown DC servos with the OpenRB-150 and without proper wiring diagrams.
Please note that the OpenRB-150 is equivalent to the Arduino MKR ZERO so these questions are better searched on the Arduino Forum instead. Most likely, they are going to recommend to use pinMode() to set the wanted pins into OUTPUT mode then to use DigitalWrite() or AnalogWrite() to put them into LOW states (all this to be done inside setup() of course).