list	p=16f690 
		#include <p16f690.inc>
		__CONFIG -_MCLRE_ON & _CP_OFF & _WDT_OFF & _INTRC_OSC_NOCLKOUT
		ERRORLEVEL -302

	cblock	0x20
		temp	
		display	
		count	
	endc

;**************************STEUP THE CONSTANTS*******************************  

		org	0x00		;this is where we come on power up and reset
		goto	Main

;**************************INTRUPT ROUTINE************************************  

		org	0x04

		movwf	temp   		;this and the lable Loop will run simultenously
					;move w into f in case to there was someting in  
					;count(see first step of Loop) 

		incf	count,f  	;increase count by 1 and put result in count
		movlw	.10   		;load w with decimal 10
		subwf	count,w  	;subtract count from w and place result in w
		btfss	STATUS,C  	;if in above operation count<= w then carry bit 
					;is set, so check for that and skip next step 
					;if it is set 
		goto	carry_on
		goto	clear

carry_on:
		bcf	INTCON,0x01   	;clear the INTF, just in case(read tuto. 11)
		movfw	temp   		;move temp to w 
		retfie			;get out of intrupt loop (this will start over 
					; the whole INTRUPT LOOP again 
clear:
		clrf	count   	;set count to 0
		bcf	INTCON,0x01  	;clear INTF
		retfie
;*****************************MAIN PROGRAMME************************  
Main:

;*****************************SET UP THE INTRUP REGISTERS***********  

		bsf	INTCON,0x07  	; set globel intrupt (tell PIC that we will use intrupts)
		bsf	INTCON,0x04  	;
		bcf	INTCON,0x01

;******************************SET UP THE PORTS**********************  
		bsf	STATUS,RP0
		movlw	b'10000000'
		movwf	TRISC
		movlw	b'00000100'
		movwf	TRISA	;set RA2 as input (for interrupt)
		bcf 	STATUS,RP0
		bsf	STATUS,RP1
		bcf	OPTION_REG,0x07
		bsf	WPUA,0x02		             
                         clrf 	     ANSEL
	             bcf           STATUS,RP1
;******************************NOW SEND THE VALUE OF COUNT TO PORTC**  

Loop:
		movf	count,w
		movwf	PORTC
		goto	Loop
		END

list p=16f628
		#include<p16f628.inc>
		__CONFIG  _MCLRE_ON & _CP_OFF & _WDT_OFF & _INTRC_OSC_NOCLKOUT
		ERRORLEVEL   -302
		cblock	0x20
			temp       
  		endc
;******************************************************************
	org 0x00
	goto main
;***********************************INTERRUPT LOOP*****************
	org 0X04
inter:
	movlw b'10000000'
	movwf PORTA				;set pin 7 of port a HIGH
	goto	inter
main:
	bsf	INTCON,0x07
	bsf INTCON,0x03
	bcf	INTCON,0x00
;**********************************SET UP THE PORTS *****************
	bsf	STATUS,RP0			;switch to BANK 1
	movlw b'00000001'	
	movwf TRISB				;set RB0 as input
	movlw b'00000000'
	movwf TRISA                                               ;set PORT A all output
	bcf OPTION_REG,0x07			
	bcf STATUS,RP0			;back to BANK 0
	movlw 0x07
	movwf CMCON				

Loop:
	movlw b'00000001'		
	movwf PORTA				;set pin 0 of port a HIGH
	goto Loop
	END