C Example: Digital Outputs - Revision history

LIMS at 20:27, 25 June 2007

2007-06-25T20:27:49Z

LIMS at 20:27, 25 June 2007

2007-06-25T20:27:15Z

LIMS at 20:26, 25 June 2007

2007-06-25T20:26:18Z

LIMS at 20:25, 25 June 2007

2007-06-25T20:25:54Z

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__TOC__
==Code==
Program to blink one LED on and off every half second.

First include header file with definitions for specific PIC.
Set fuses. HS is type of external clock, low voltage protection
(LVP) is off, and the watchdog timer (WDT) is off.
External clock frequency of 20 MHz is specified.

#include <18f4520.h>
#fuses HS,NOLVP,NOWDT
#use delay (clock=20000000)

// Define pin names to be used in the main program. See header file
// for currently defined pin names.

#define LED_0 PIN_C0

// Begin main body of program. Notice main is a function of "void". This
// is a more explicit way of saying main is a function of nothing. Using
// main() is equivalent. Every program is required to have a function
// called "main".

void main(void) {

// Setup an infinite loop, using a while statement.

while(TRUE){

// Turn LED on and off by setting its pin low or high, with a delay
// between each switching.

output_low(LED_0);
delay_ms(500);
output_high(LED_0);
delay_ms(500);}
}

@@ Line 36: / Line 36: @@
          delay_ms(500);}
    }
+==Associated Circuitry==

@@ Line 12: / Line 12: @@
    #use delay (clock=20000000)
-// Define pin names to be used in the main program. See header file
+Define pin names to be used in the main program. See header file
-// for currently defined pin names.
+for currently defined pin names.
-#define LED_0 PIN_C0
+   #define LED_0 PIN_C0
-// Begin main body of program.  Notice main is a function of "void".  This
+Begin main body of program.  Notice main is a function of "void".  This
-// is a more explicit way of saying main is a function of nothing.  Using
+is a more explicit way of saying main is a function of nothing.  Using
-// main() is equivalent.  Every program is required to have a function
+main() is equivalent.  Every program is required to have a function
-// called "main".
+called "main".
-void main(void) {
+   void main(void) {
-   // Setup an infinite loop, using a while statement.
+Setup an infinite loop, using a while statement.
-   while(TRUE){
+      while(TRUE){
-      // Turn LED on and off by setting its pin low or high, with a delay
+Turn LED on and off by setting its pin low or high, with a delay
-      // between each switching.
+between each switching.
-      output_low(LED_0);
+         output_low(LED_0);
-      delay_ms(500);
+         delay_ms(500);
-      output_high(LED_0);
+         output_high(LED_0);
-      delay_ms(500);}
+         delay_ms(500);}
-}
+   }

@@ Line 8: / Line 8: @@
 External clock frequency of 20 MHz is specified.
-#include <18f4520.h>
+   #include <18f4520.h>
-#fuses HS,NOLVP,NOWDT
+   #fuses HS,NOLVP,NOWDT
-#use delay (clock=20000000)
+   #use delay (clock=20000000)
 // Define pin names to be used in the main program. See header file