daima30.asm

<MCS-51系列单片机应用及接口技术>书中的源代码

	ORG	2080H
START:	LD	SP,#0FFH
	LD	IOC1,#50H
	LD	40H,#0
	LD	42H,#1
	LD	44H,#2
	LD	46H,#3
	LD	48H,#4
	LD	4AH,#5
	LDB	HSO_COMMAND,#2CH  ；数码管全亮
	ADD	HSO_TIME,TIMER1,#03H
	NOP
	LDB	HSO_COMMAND,#0CH  ；数码管全灭
	ADD	HSO_TIME,TIMER1,#03H
	NOP
	NOP
HERE:	LCALL	DISPLAY	
	SJMP	HERE
;
DISPLAY:DB	P1,TAB[40H]             ；读字形
	LDB	HSO_COMMAND,#00H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.0立即置零
	NOP
	NOP
	LCALL	DELAY                  ；延时
	LDB	HSO_COMMAND,#20H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.0置1
	NOP
	NOP
;
	LDB	P1,TAB[42H]
	LDB	HSO_COMMAND,#01H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.1立即置零
	NOP
	NOP
	LCALL	DELAY                  ；延时
	LDB	HSO_COMMAND,#21H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.1置1
	NOP
	NOP
;
	LDB	P1,TAB[44H]
	ORB	P1,#01H
	LDB	HSO_COMMAND,#02H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.2立即置零
	NOP
	NOP
	LCALL	DELAY                  ；延时
	LDB	HSO_COMMAND,#22H
	ADD	HSO_TIME,TIMER1,#03H
	NOP
	NOP
;
	LDB	P1,TAB[46H]
	LDB	HSO_COMMAND,#03H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.3置零
	NOP
	NOP
	LCALL	DELAY                  ；延时
	LDB	HSO_COMMAND,#23H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.3立即置1
	NOP
	NOP
;
	LDB	P1,TAB[48H]
	ORB	P1,#01H
	LDB	HSO_COMMAND,#04H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.4置零
	NOP
	NOP
	LCALL	DELAY                  ；延时
	LDB	HSO_COMMAND,#24H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.4立即置1
	NOP
	NOP
;
	LDB	P1,TAB[4AH]
	LDB	HSO_COMMAND,#05H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.5置零
	NOP
	NOP
	LCALL	DELAY                  ；延时
	LDB	HSO_COMMAND,#25H
	ADD	HSO_TIME,TIMER1,#03H  ；HSO.5立即置1
	NOP
	NOP
	RET
DELAY:	LDB	AL,#255                  ；延时子程序
DELAY1:	NOP
	NOP
	DJNZ	AL,DELAY1
	RET
;========TAB====================================   字形表
TAB:	DCB	0FCH,60H,0DAH,0F2H,66H
	DCB	0B6H,0BEH,0E0H,0FEH,0F6H
        END
动态扫描显示必须由CPU不断地调用显示程序，才能保证持续不断的显示。和静态显示相比，动态扫描的程序稍有点复杂。