L298N HELP!!??

Using Arduino Motors, Mechanics, Power and CNC
1

So, I completed the getting started with Arduino guide and exercises. I proceeded to buy the L298N motor shield and two small dc motors (not steppers) and two Photo resistors. I am trying to make a basic photovore that will determine engine speed based on light level for each side and thereby steer. Fairly straightforward or so one would assume. I am going to be hooking up the motors to the a and b motor drivers on the L298N. I am currently trying to figure out how to control speed. I am using this code at present, which I found on some site:

int pwm_a = 3;  //PWM control for motor outputs 1 and 2 is on digital pin 3 (or 5,6)
int pwm_b = 9;  //PWM control for motor outputs 3 and 4 is on digital pin 9 (or 10,11)
int dir_a = 2;  //direction control for motor outputs 1 and 2 is on digital pin 2 (or 4,7)
int dir_b = 8;  //direction control for motor outputs 3 and 4 is on digital pin 8 (or 12,13)

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);
}

at this point I only have one motor hooked up and 9v batter going to the Uno board. The motor is hooked up to A, and I can hear it engage and the LED is lighting, however the motor is not rotating. I beesech one kind soul to hook me up with a working code snippet to drive the motor, and I can figure out the rest from there. Much thanks.

2

Unfortunately there is no basic guide to this chip that I have boon able to find, hell if I had the knowledge I would write one. Unfortunately I am a newbie in the world of arduino, this is only my second day working with the board, and first with the L298N.

3 
void loop()
{
analogWrite(pwm_a, 255);  //set both motors to run at 100% duty cycle (fast)
}

haha the problem has that I ripped this motor out of a broken nano helicopter and the prong was bent, had to move it a bit now it works

4

bytedisorder:
Unfortunately there is no basic guide to this chip that I have boon able to find, hell if I had the knowledge I would write one. Unfortunately I am a newbie in the world of arduino, this is only my second day working with the board, and first with the L298N.

The datasheet isn't clear enough...?