//Robot moves toward the light

int leftspeed;
int rightspeed;
int diff;
#define leftL analog(3)
#define rightL analog(2)

// if left is brighter, diff becomes negative.
// if right is brighter, diff becomes positive.
// the brighter the sensor the lower the analog voltage.
// 2550 equals zero servo speed.

void main()
{
    init_expbd_servos(1);
    msleep (3000L);
    
    while(1)
      { 
        diff = leftL-rightL;
        printf ("left%d right%d diff%d",leftL,rightL,diff);
        msleep(500L);
        printf("\n");
        leftspeed = 50 + diff;
        rightspeed = 50 - diff;
        servo0 = 2550 + leftspeed;
        servo1 = 2550 - rightspeed;
        
        
    }
}