/*------------------------------------------------------------------\
|                                                                   |
| A very simple program to produce a roaming bug demo for the RCX.  |
| It assumes the robot has one touch sensor and one light sensor    |
| (the light sensor is not used).                                   |
|                                                                   |
| The robot heads forward until it hits an obstacle, then backs up  |
| spins, and heads off again in the new direction.                  |
|                                                                   |
| Simon Parsons                                                     |
| City University of New York                                       |
| February 2006                                                     |
|                                                                   |
\------------------------------------------------------------------*/

// Define sensor ports

#define BUMP	SENSOR_1
#define EYE 	SENSOR_3

// Define motor ports

#define LEFT_MOTOR	OUT_A
#define RIGHT_MOTOR	OUT_C

// Set light sensor threshold

#define STOP_THRESHOLD	40

task main()
{

 // Initialise sensors
 
	SetSensor(BUMP, SENSOR_TOUCH);
	SetSensor(EYE, SENSOR_LIGHT);

 //Switch on motors
 
	OnFwd(LEFT_MOTOR+RIGHT_MOTOR);

	while(true)
	{
	
  // While the touch sensor is not activated, just keep going
  
		if (BUMP == 1)
		{

      // Once we hit something, switch motors off, then switch them on
      // in reverse and wait for a while.
    
  		Off(LEFT_MOTOR+RIGHT_MOTOR);
			OnRev(LEFT_MOTOR+RIGHT_MOTOR);
			Wait(200);

      // Now switch the motors off again, and switch them on in opposite
      // directions to turn the robot, again wait a while.
    
    	Off(LEFT_MOTOR+RIGHT_MOTOR);
			OnFwd(LEFT_MOTOR);
			OnRev(RIGHT_MOTOR);
			Wait(100);
			
      // Now switch the motor that was in reverse, to go forward.
      
      Off(RIGHT_MOTOR);
			OnFwd(RIGHT_MOTOR);
		}
	}
}