;******************************************************
;*               LED_INC1.ASM
;* PORTC外接LED，輸出值由0開始每隔一段Delay時間加1
;******************************************************
		list p=16F877		
#include 	<p16f877.inc>
;
VAL_US		equ	.249			; 1ms delay 給定初值
VAL_MS		equ	.250			; 呼叫1ms Delay之次數
count		equ	0x20		; 1ms delay 變數位址
count_ms		equ	0x21   		 ; 呼叫1ms Delay之變數位址.

;
;******  程式開始 *********************
			org 	0x00		; reset vector
			nop               ; Reserve for MPLAB-ICD
initial:	
			banksel	TRISC	; Select to bank1
			clrf	TRISC		; PORTC = Output
		banksel PORTC 	; Select to bank0
			clrf	PORTC		; Clear PORTC
start:
			incf	PORTC,f		; PORTC = PORTC + 1
		call 	delay_250ms	; Call delay routine
			goto	start
;



;-------- 250 ms delay routine ----------
delay_250ms:	
			movlw	VAL_MS		 
		movwf	count_ms
loop_ms		call 	delay_1ms
			decfsz	count_ms,f
			goto	loop_ms
		return
;
;-------- 1 ms delay routine -----------
delay_1ms:
			nop			 
		movlw	VAL_US		 		
			movwf	count
dec_loop	nop
			decfsz	count,f
		goto 	dec_loop
			return
;	
			end