I have a 2 wire Vex motor and a motor controller 29 which is basically a H bridge. I am using the servo library because they say with this motor controller 29 it should work like a servo. In my code I am using the .write method of my servo object. I am writing the code to move the motor forward for 3 seconds and stop for 3 seconds and then backwards for 3 seconds. When I measure the output of the motor controller 29 it shows +7.4 volts and then a very low MA that keeps changing and then -7.4 volts. That is basically what I programmed but when I plug it into the motor the motor makes a sound like it has very little voltage that is not enough to move it and it does not move. The motors work fine if I hook them directly to the battery.
I have tried 2 different battery configurations. A 6 V for the motor and a 9 V for the Arduino. I have also tried powering both off the 9 V. I tried to find an answer online and tried wiring a low pass filter with a 1K resistor and a 1uF compositor to the output of the arduino. That did get the motor moving but only in only 1 direction and the output I measure is now + 7.4 volts and the pause then +7.4 volts again and does not reverse the polarity. Can anybody please make any suggestions on how to solve this problem?