ServoCape and BBB/General


Is the ServoCape able to push multiple servos at once, i.e. 10 or 12? I know what the ServoCape is intended for currently but I am having a complication w/ running one servo and then running multiple servos right after one another in source.

As soon as I run the source in a server, the server starts and then the board shuts down on its own once I click a radio button on the server.

I am basically looking for feedback on an issue pertaining to handling the ServoCape and BBB.


P.S. Could it be that the ServoCape does not provide adequate protection against current to the BBB?

It will depend on your servo motors.

What is the current rating of your power supply and motors?

If you stall the motor it will take more current.
Can you move more than 1 with nothing connected to them ?

Hello Sir,

Seth here. Here are the specs. on the motors in question:

Stall Torque (5V): 19 kg/cm (263.8oz/in)
Stall Torque (6.8V): 21.5 kg/cm (298.5 oz/in)
Dead band: 3μs
Speed : 0.16 sec/60°(5V) / 0.14 sec/60°(6.8V)
Operating Voltage: 4.8 ~ 6.8 DC Volts
Weight: 60 g (2.12 oz)
Motor Type: DC Motor
Working frequence: 1520μs / 333hz

So, it seems I am w/in operating voltages. I can move the motors when not connected to anything.

W/ their current configuration, mechanical parts and hardware, I can alter the state of the motors w/ no power applied to them.


P.S. My power supply is 5v to the ServoCape from the BBB. This may be the issue. I also have the barrel jack connected which is 5v @ 1A.

Hello Sir,

@benedict.hewson , it is most likely a hardware issue, i.e. not BBB related. I will check and return service.


P.S. I am lucky I did not fry the BBB by accident. I am sure there was some sort of reverse surge. Phew.

Okay Sir,

It is indeed my issue and not the BBB or ServoCape or the source. My backward incompatible configuration of hardware was doing the ill-fated surging and killing off the BBB when it could not understand what was happening.


P.S. I will work on the hardware and get to making some error codes too. Sorry to act like I was right when I was wrong! At least for those of us who use the ServoCape, by my standards anyways, we can say now it is 100% fully functional!


The board dies still w/out my hardware components attached to the servos. For instance, if I put in the source to handle moving two motors at once, it dies. If I move each motor separately, everything works fine.

Sheesh and Another Update

Okay so, I found that the angle (angle 0 in this case) is awkward for now (for no better terminology b/c of my lack of understanding so far). The percentage is working just fine for each motor.

Angle used to work but no longer works for some reason. I have not figured out quite why just yet.

Anyway, maybe 0 is stall torque and creates a rush of reverse polarity. I am guessing, i.e. as I have not tested yet.