A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge Power Options

A-Star 32U4 Robot Controller SV with Raspberry Pi Bridge

A few newbie questions, if I may…

The user’s guide warns to not connect multiple power sources… does this mean that I cannot connect to a computer with the USB if I have a battery connected to the 6-pin strip of terminal blocks at PWR+ (motor power) and am powering both the A-Star 32U4 and attached Raspberry Pi?

Similarly, referencing:
"Power provided to the Raspberry Pi can be switched off by driving the Raspberry Pi shutdown pin, RPISHDN, to 5 V."

So if while testing and rebooting and I do not want the attached Raspberry Pi to boot up I can just connect RPISHDN to onboard 5 V with a spare wire or shoudl I just remove the MicroSD so that it can’t boot?


That warning is specifically for the multiple Power In/PWR+ locations on the board (like the barrel jack and the power connections on the 6-pin strip of screw terminals). It is safe to have any combination of A-Star USB power, A-Star external power (the “Power In” connections), and Raspberry Pi USB power connected to the system.

You can connect RPISHDN to any 5V source that shares a ground with the rest of the system (like the A-Star’s 5V supply) to prevent the robot controller from powering the Raspberry Pi.


Sorry, meant to log on and thank you when you answered, just the answer I needed, thanks!