PicWiser Ultimate Guide To Learning Embedded C Programming

The program on the right shows how this is done. Note that basically we just added more 1's to the port setting statement (as well as changed from PORTC to PORTB).

Nothing real earth shattering hear but what happened to the delay functions we just introduced?

What we'd like to look at now is reusing the delay functions by putting them in a separate file so we can share the functions with other programs.

The second line in the program is another #include statement but it's different from the first one. The first one has the include file name in brackets <> which tells the compiler to find it in one of it's standard search directories. The 2^nd line has the file name in double quotes which tells the compiler that it should find it stored with the project.

#include <htc.h>
#include "delay.h"
//------------------------------------
// file: led4_1.c
// description: This is the C code
// for the 4 LED project
// author: Emicros
//------------------------------------
/*------------------------------------
** function: TimerISR
** description: This is just a place
** holder for now and isn't used in
** the program.
**----------------------------------*/
void interrupt TimerISR( void )
{
   if( (TMR1IE) && (TMR1IF) )
   {
      TMR1IF = 0;
   }
}
/*-----------------------------------
** function: main()
** description: Main function.
**----------------------------------*/
void main( void )
{
   TRISB = 0b00001111;
   TRISC = 0b11111011;
   while( 1 )
   {
        /* turn on the 4 leds */
      PORTB = 0b11110000;
      PORTC = 0b00000100;
           delay_ms( 50 );
           /* turn off the 4 leds */
      PORTB = 0b00000000;
      PORTC = 0b00000000;
          delay_ms( 50 );
   }
}