On Board LEDs

The board has 5 onboard LEDs generally used to show the status of line sensors, that means when a black line comes just in the front of line sensor, corresponding LED is turned on. Each LED has a numeric id between 1-5.

LED id	PCB Marking	MCU I/O
1	D9 LEFT MOST	PD7
2	D8	PD6
3	D7	PD5
4	D6	PD4
5	D5 RIGHT MOST	PB0

 

LEDs can be controlled using the LED library that comes in as following files.

• led.c
• led.h

You can get these files from the lib folder in the DVD.

To use the LED Library do the following :-

1. Create a new folder lib in the project using Solution Explorer.
2. Create a new sub folder led inside the lib folder.
3. Using Windows File Manager copy/paste the led.c and led.h files to your <project folder>/lib/led/ from the DVD.
4. Add both files to your projects under lib/led.
5. Now you are ready to use the library!

Using the LED library

The led library has following three functions.

void LEDInit(void)

This function initializes the i/o port drivers that are connected to LEDs. This function must 
be called before any of the functions below.

Arguments:
NONE

Returns:
NONE

    

---

 

void LEDOff(uint8_t id)

Turns off the LED referred by id. 
Arguments:
	id
	Type: uint8_t (unsigned 8 bit integer)
	Valid Range: 1-5

Returns:
NONE

    

---

void LEDOn(uint8_t id)

Turns on the LED referred by id. 
Arguments:
	id
	Type: uint8_t (unsigned 8 bit integer)
	Valid Range: 1-5

Returns:
NONE

    

---

Sample Program

The following sample program turns on each LED from id 1 to 5, then turns them off one by one from id 1 to 5.

/******************************************************************************

LFR Board Sample Programs

------------------------------------


Description :  The following sample program turns on each LED from id 1 to 5, 
            then turns them off one by one from id 1 to 5.

            This whole process is repeated again and again.


Author      : Avinash Gupta 2012
Web         : www.eXtremeElectronics.co.in

******************************************************************************/
#include <avr/io.h>
#include <util/delay.h>

#include "lib/led/led.h"

void Wait();

int main(void)
{
   LEDInit();

    while(1)
    {
        uint8_t i;

      for (i=1;i<=5;i++)
      {
         LEDOn(i);

         Wait();
      }

      for (i=5;i>0;i--)
      {
         LEDOff(i);

         Wait();
      }

    }
}

void Wait()
{
   uint8_t i;

   for(i=0;i<30;i++)
   {
      _delay_loop_2(0);
   }

}

HEX File Ready to Burn

The hex file ready to burn can be found in the Precompiled HEX Files folder in the Support DVD.

• LEDDemo1.hex

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