Ardumoto Short?

Hi all,

I recieved an ardumoto yesterday and wired it up today. To test I ran the sample code from sparkfun. Ardumoto_test_3.pde.

12VDC 1A wall wart to the Ardumoto

USB 5V to Arduino

I am using the Tamiya twin motor gear box at the moment and the toy motor that came with an Arduino Inventors Kit to test.

When running the sketch with no load my LED’s indicating direction light up and appear to follow the code.

Blue LED on B while Yellow on A

Then Yellow on B while Blue on A.

No LED’s on the same channel are on at the same time.

When I put a load, either the Tamiya’s or the toy motor, I only get one direction and both leds will light up, one dimly the other brightly, and motors will turn in only one direction.

Does anyone have any ideas as to the direction I should take as to the issue? It seems to be shorting under load only. Let me know if I am missing any critical information, Working on checking current draws now.

Thanks

/*
  10-5-10
  Pete Dokter
  SparkFun Electronics
  
  This is an example sketch for Arduino that shows very basically how to control an Ardumoto
  motor driver shield with a 5V Arduino controller board (3.3V may work, but it's out of spec
  for the L298 H-bridge logic, so no promises). If you're plugging the Ardumoto into an
  Arduino Duemilanove or similar, all the connections are done for you and you can just rewrite
  the examples in this code to your liking.
  
  Changed to reflect a new board revision...
*/


//int pwm_a = 10;  //PWM control for motor outputs 1 and 2 is on digital pin 10
int pwm_a = 3;  //PWM control for motor outputs 1 and 2 is on digital pin 3
int pwm_b = 11;  //PWM control for motor outputs 3 and 4 is on digital pin 11
int dir_a = 12;  //direction control for motor outputs 1 and 2 is on digital pin 12
int dir_b = 13;  //direction control for motor outputs 3 and 4 is on digital pin 13


void setup()
{
  pinMode(pwm_a, OUTPUT);  //Set control pins to be outputs
  pinMode(pwm_b, OUTPUT);
  pinMode(dir_a, OUTPUT);
  pinMode(dir_b, OUTPUT);
  
  analogWrite(pwm_a, 100);  //set both motors to run at (100/255 = 39)% duty cycle (slow)
  analogWrite(pwm_b, 100);
  
}

void loop()
{
  digitalWrite(dir_a, LOW);  //Set motor direction, 1 low, 2 high
  digitalWrite(dir_b, LOW);  //Set motor direction, 3 high, 4 low
  
  delay(1000);
  
  analogWrite(pwm_a, 255);  //set both motors to run at 100% duty cycle (fast)
  analogWrite(pwm_b, 255);
  
  delay(1000);
  
  digitalWrite(dir_a, HIGH);  //Reverse motor direction, 1 high, 2 low
  digitalWrite(dir_b, HIGH);  //Reverse motor direction, 3 low, 4 high
  
  delay(1000);
  
  analogWrite(pwm_a, 100);  //set both motors to run at (100/255 = 39)% duty cycle
  analogWrite(pwm_b, 100);
  
  delay(1000);
}

Please disregard above, I didn’t have my 5VDC power regulator wired correctly. 12v to a 3to 6V, 2A motor means bad things for a 2A motor controller.