ckmain.c

Hitech microchip PIC C18 Compiler

#include <htc.h>
#include "cksum.h"

/** A simple example of how one can runtime-verify a checksum
 * that was generated using the compiler's --checksum option
 * The pre-compiled result is found in the const variable, _checksum0.
 * The header, cksum.h has settings that need to be adjusted to match the
 * --checksum specifications.
 */
void main(void){
	TRISB = 0;		// output mode
	PORTB = 0xFF;
	if( cksum() != _checksum0){
		while(1);	// checksum error - no effect on PORTB
		/* My calculated checksum doesn't match the pre-compiled result...
		 * 1) do all of the variables in cksum.h match the --checksum settings?
		 * 2) are the ranges of calculation realistic?
		 * 3) the size of calculation range should be a multiple of the algorithm variable.
		 */
	}else{
		unsigned int delay;
		while(1){ 	// success
			for(delay=1000;delay;delay--)
				PORTB ^= 0xFF;	// blink all of PORTB
		}
	}
}