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;    Filename:	   main.asm                                           *
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;    Author:                                                          *
;    Company:                                                         *
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;**********************************************************************
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;    Files required:                                                  *
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;; basic setup
	list      p=16f676           ; list directive to define processor
	#include <p16F676.inc>        ; processor specific variable definitions

	errorlevel  -302              ; suppress message 302 from list file

	__CONFIG   _CP_OFF & _CPD_OFF & _BODEN_OFF & _MCLRE_OFF & _WDT_OFF & _PWRTE_ON & _INTRC_OSC_NOCLKOUT 

; '__CONFIG' directive is used to embed configuration word within .asm file.
; The lables following the directive are located in the respective .inc file.
; See data sheet for additional information on configuration word settings.

w_temp        EQU     0x20        ; variable used for context saving 
status_temp   EQU     0x21        ; variable used for context saving

		ORG     0x000             ; processor reset vector
		goto    main              ; go to beginning of program
	

		ORG     0x004             ; interrupt vector location
		movwf   w_temp            ; save off current W register contents
		movf	STATUS,w          ; move status register into W register
		movwf	status_temp       ; save off contents of STATUS register

; isr code can go here or be located as a call subroutine elsewhere

		movf    status_temp,w     ; retrieve copy of STATUS register
		movwf	STATUS            ; restore pre-isr STATUS register contents
		swapf   w_temp,f
		swapf   w_temp,w          ; restore pre-isr W register contents
		retfie                    ; return from interrupt


; these first 4 instructions are not required if the internal oscillator is not used
main
;		call    0x3FF             ; retrieve factory calibration value
;		bsf     STATUS,RP0        ; set file register bank to 1 
;		movwf   OSCCAL            ; update register with factory cal value 
;		bcf     STATUS,RP0        ; set file register bank to 0


;; remaining code goes here



;; initialize eeprom locations

		ORG	0x2100
		DE	0x00, 0x01, 0x02, 0x03


		END                       ; directive 'end of program'