ch10_t6.asm

51单片机基础篇 对于有一定基础的人看看 包含书中所以的源代码

     ;PROGRAM NAME:T6.ASM
     ;TEST TIMER0 MODE 1:16 BIT COUNT UP
     ;
     MS_10		EQU	30H
     COUNT		EQU	9217			;10ms FOR XTAL=11.0592MHz
     CHECK_BIT 	REG	P3.2
     LED		REG	P3.7
     ;
     	 		ORG	0
     			MOV	R0, #00H
     			DJNZ	R0, $			;WAIT
     			CLR	CHECK_BIT
     			MOV	SP, #40H
     			MOV 	MS_10, #00H		;CLEAR(MS_10)
     ;
     			MOV	A, TMOD
     			ANL 	A, #11110000B
     			CLR	ACC.3			;GATE=0
     			CLR	ACC.2			;C/T=0
     			CLR	ACC.1			;TIMER0 M1=0
     			SETB	ACC.0			;TIMER0 M0=1
     			MOV	TMOD, A
     			MOV	TH0, #(65536-COUNT)/256
     			MOV	TL0, #(65536-COUNT).MOD.256
     			CLR	TF0			;CLEAR TF0
     			SETB	TR0
     ;
     LOOP		JNB	TF0, LOOP		;TF0=0
     ;TF0=1
     OVER		CLR	TF0			;CLEAR TF0
     			MOV	TH0, #(65536-COUNT)/256
     			MOV	TL0, #(65536-COUNT).MOD.256
     			INC	MS_10			;INCREMENT COUNT
     			MOV	A, MS_10
     			CJNE	A, #10, $TEST
     $TEST		JNC	$LEDOFF
     			SETB	LED 			;LED ON
     			SJMP	$CONT
     $LEDOFF 		CLR 	LED			;LED OFF
     ;
     $CONT 		MOV	A, MS_10
     			CJNE	A, #100, $NEXT
     			CPL	CHECK_BIT		;P3.2 COMPLENENT
     			MOV	MS_10, #00H 	        ;CLEAR COUNT
     $NEXT 		SJMP	LOOP
     ;