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skhaja 0 Newbie Poster

I am having difficulty in using the btfsc commands. I am suppose to use them to to program a circuit with 8 LEDs so that they can sequentially light up.

Well, you can say that I am half way there as so far only the first four (RC0-RC3) work while the rest are untouched.

Can anyone help please?
below is the attached asm file.

Thanks.

;**********************************************************
; Lab03b.asm
; Dan Simon
; Cleveland State University
;
; This program repeatedly blinks the LEDs that are connected 
; to RC0, RC1, and RC2, in order. This program illustrates
; how a lookup table can be implemented in the PIC.
;**********************************************************

	list p=16f877
	include "p16f877.inc"

HalfSec		equ	D'50'		; Number of centiseconds in half a second 
FirstLED 	equ	B'00000001'	; PORTC mask for the first LED
CountOuter0	equ	D'10'
CountInner0	equ	D'250'

	cblock	0x20
		BLNKCNT			;LED loop counter
		CountOuter
		CountInner
	endc

	org	0x00		;Reset vector
	nop
	goto	Main		

	org	0x04		;Unused interrupt vector

;;;;;;; BlinkTable subroutine  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; This subroutine reads PORTC and retains only the 3 LSBs.  It uses them to 
; access the table.  It returns in W the bits of PORTC to be toggled.

BlinkTable
	btfsc	PORTC,0	;	
	btfsc	PORTC,3	;	
	btfsc	PORTC,0	;
	
;;;;;;; Main program ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

Main
	call	Initial		;Initialize everything
MainLoop	
	call	Blink		;Blink LED
	call	TenMs		;Insert ten millisecond delay
	goto	MainLoop	;Do it again

;;;;;;;	Initial subroutine ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; This subroutine performs all initializations of variables and registers.

Initial	
	movlw	HalfSec		;Initialize first blink of LED
	movwf	BLNKCNT		; to last about 0.50 seconds
	movlw	FirstLED	;Turn on the first LED; turn off others
	movwf	PORTC
	banksel	TRISC		;Set register access to bank 1
	clrf 	TRISC      	;Set up all bits of PORTC as outputs
	banksel	PORTA		;Set register access back to bank 0
	return

;;;;;;; Blink subroutine ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; This subroutine changes PORTC every 0.5 second.

Blink 	
	decfsz	BLNKCNT,F	;Decrement loop counter and return if not zero
	goto	BlinkEnd
	movlw	HalfSec		;Reinitialize BLNKCNT
	movwf	BLNKCNT
	rlf	PORTC,W		;Toggle the First LED
	movwf	PORTC	
BlinkEnd	
	return

;;;;;;; TenMs subroutine ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
; This subroutine and its call inserts a delay of ten milliseconds into
; the execution of code.  It assumes a 4 MHz clock.

TenMs
	movlw	CountOuter0
	movwf	CountOuter
DecO	
	movlw	CountInner0
	movwf	CountInner
DecI	
	nop
	decfsz	CountInner, F
	goto	DecI
	decfsz	CountOuter, F
	goto	DecO	
	return

	end
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