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// prototype code for a line follower bot. Uses a very simple for loop
// to check two top-hat reflectance sensors aligned on left and right of
// the line, presumably a black tape. The #defines will have to be adjusted.
// Written THU MAY 3 2007 02:40

#define L_MOTOR 0
#define R_MOTOR 3

#define HAT_L analog(4)
#define HAT_R analog(5)
#define HAT_THRESH 135

#define V_FWD 75

void fwd(){ mav(L_MOTOR,V_FWD); mav(R_MOTOR,V_FWD); }
void left(){ mav(L_MOTOR,0); mav(R_MOTOR,V_FWD); }
void right(){ mav(L_MOTOR,V_FWD); mav(R_MOTOR,0); }

int main()
{
     for(;;)
     {
          if(HAT_L >= THRESH && HAT_R >= THRESH) fwd();
          if(HAT_L < THRESH) /* uhoh, drifted left! */ right();
          if(HAT_R < THRESH) /* uhoh, drifted right! */ left();
     }
return 0;
}