Just built Magician Chassis, but doesn't work correctly. I'm using MBED and SparkFun, Motor Driver 1A Dual TB6612FNG. Program is the Magician_Motor_Test from the Cookbook. The Sparkfun board pinouts are a bit different from the Pololu board, but I believe it it should work. So I made the change. I'm using a separate 6 volt supply for the motors and MBED, after programing it from USB connection to the PC.

Starting the program, I see LED1 correctly flashing at 1 sec intervals. Killing power, I hook up the 4 wires for the 2 motors. Powering up again, neither motor runs, both LED1 and Main MBED LED now flash fast. I disconnect one motor, and now the other motor runs, but only in one direction and then stops. The fast flashing starts again. This same action is the same with the other motor.

So, both motors will not run at the same time. Even with one motor, it will not run unless I touch the plus wire to the correct MBED pin. It will not start up by itself.

Both motors run fine without the MBED or Motor Driver, by hooking them up to 6 a volt supply directly. Please help. donde

SOLVED!

Needed a large capacitor across the Vin to ground (6.0 v external battery). Used a 100 ufd donde