Sharp / MAxBotix EZ3 Sensor Issue

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1

I have mounted 2 Sharp IR sensors on my 3Pi angled left and right with the sonar front and center.

I tried to get a sensor read of the left sensor and have it print to the LCD with the following code:

#include <pololu/3pi.h>
#include <stdio.h> 
  
 char f;
 char r;
 char buffer = 25;
 
 
int main()
{
        set_analog_mode(MODE_8_BIT);
  
       
        print("Press B"); //printing "Press B" to the LCD

  //Waiting for button to be pressed
  while (!button_is_pressed(BUTTON_B));

  wait_for_button_release(BUTTON_B); //code above is executed while button b is pressed and this code looks for the release.

   while(1)
        {  
    
        clear();

        unsigned char l = analog_read(7);

        delay_ms(1000);

        print_long (l);
    
  }
  
  return 0;

}

It will print out the “Press B”, but after button press, it goes blank.

To check to see if the sensors worked, I checked voltages - OK, then loaded the wall follower code. Even though it is set up for 2 sharp sensors, it did take off and avoid walls and objects.
Any ideas on why it won’t print to the screen?

2

Hello.

You are clearing the LCD right after you print to it; try swapping the delay_ms and print_long lines.

- Ryan

3

That did it! Thanks! With the clear on the top end, I overlooked it. I liked it so much, I used the lcd_goto and positioned all 3 sensor reads on the LCD.