/* 5/22/2012 Timothy Holmberg SparkFun Electronics This code includes the ddition of fade in and out PWM. Also a stop feature. And the addition of individual functions for motor control This was a revision of the example sketch that originated from Pete Dokter's code for Arduino that shows very basically how to control an Ardumoto motor driver shield with a 5V Arduino controller board. http://www.sparkfun.com/datasheets/DevTools/Arduino/Ardumoto_test_3.pde This also includes parts of the Fading Example, Created 1 Nov 2008 By David A. Mellis, modified 30 Aug 2011 By Tom Igoe http://arduino.cc/en/Tutorial/Fading */ 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 int val = 0; //value for fade 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() { forw(); //Set Motors to go forward Note : No pwm is defined with the for function, so that fade in and out works fadein(); //fade in from 0-255 delay(1000); forward(); //continue full speed forward delay(1000); fadeout(); //Fade out from 255-0 delay(1000); //Wait one second stopped(); // stop for 2 seconds delay(2000); back(); //Set motors to revers. Note : No pwm is defined with the back function, so that fade in and out works fadein(); //fade in from 0-255 delay(1000); backward(); //full speed backward delay(1000); fadeout(); //Fade out from 255-0 delay(1000); } /* Let's take a moment to talk about these functions. The forw and back functions are simply designating the direction the motors will turn once they are fed a PWM signal. If you only call the forw, or back functions, you will not see the motors turn. On a similar note the fade in and out functions will only change PWM, so you need to consider the direction you were last set to. In the code above, you might have noticed that I called forw and fade in the same grouping. You will want to call a new direction, and then declare your pwm fade. There is also a stop function. */ void forw() // no pwm defined { digitalWrite(dir_a, HIGH); //Reverse motor direction, 1 high, 2 low digitalWrite(dir_b, HIGH); //Reverse motor direction, 3 low, 4 high } void back() // no pwm defined { digitalWrite(dir_a, LOW); //Set motor direction, 1 low, 2 high digitalWrite(dir_b, LOW); //Set motor direction, 3 high, 4 low } void forward() //full speed forward { digitalWrite(dir_a, HIGH); //Reverse motor direction, 1 high, 2 low digitalWrite(dir_b, HIGH); //Reverse motor direction, 3 low, 4 high analogWrite(pwm_a, 255); //set both motors to run at (100/255 = 39)% duty cycle analogWrite(pwm_b, 255); } void backward() //full speed backward { digitalWrite(dir_a, LOW); //Set motor direction, 1 low, 2 high digitalWrite(dir_b, LOW); //Set motor direction, 3 high, 4 low analogWrite(pwm_a, 255); //set both motors to run at 100% duty cycle (fast) analogWrite(pwm_b, 255); } void stopped() //stop { digitalWrite(dir_a, LOW); //Set motor direction, 1 low, 2 high digitalWrite(dir_b, LOW); //Set motor direction, 3 high, 4 low analogWrite(pwm_a, 0); //set both motors to run at 100% duty cycle (fast) analogWrite(pwm_b, 0); } void fadein() { // fade in from min to max in increments of 5 points: for(int fadeValue = 0 ; fadeValue <= 255; fadeValue +=5) { // sets the value (range from 0 to 255): analogWrite(pwm_a, fadeValue); analogWrite(pwm_b, fadeValue); // wait for 30 milliseconds to see the dimming effect delay(30); } } void fadeout() { // fade out from max to min in increments of 5 points: for(int fadeValue = 255 ; fadeValue >= 0; fadeValue -=5) { // sets the value (range from 0 to 255): analogWrite(pwm_a, fadeValue); analogWrite(pwm_b, fadeValue); // wait for 30 milliseconds to see the dimming effect delay(30); } } void astop() //stop motor A { analogWrite(pwm_a, 0); //set both motors to run at 100% duty cycle (fast) } void bstop() //stop motor B { analogWrite(pwm_b, 0); //set both motors to run at 100% duty cycle (fast) }