counter.asm

单片机MSC51设计的5个源程序：1、数据排序2、多功能数字钟设计3、P1口循环亮灯设计4、脉冲计数器5、8250芯片串口扩展。另附程序详细介绍。

	ORG 06E0H
SE15:	MOV SP,#53H
	MOV TMOD,#05H
	MOV TH0,#00H
	MOV TL0,#00H
	SETB TR0
LO29:	MOV R2,TH0
	MOV R3,TL0
	LCALL ZOY0
	MOV R0,#79H
	MOV A,R6
	LCALL PTDS
	MOV A,R5
	LCALL PTDS
	MOV A,R4
	LCALL PTDS
	LCALL SSEE
	SJMP LO29
ZOY0:	CLR A
	MOV R4,A
	MOV R5,A
	MOV R6,A
	MOV R7,#10H
LO30:	CLR C
	MOV A,R3
	RLC A
	MOV R3,A
	MOV A,R2
	RLC A
	MOV R2,A
	MOV A,R6
	ADDC A,R6
	DA A
	MOV R6,A
	MOV A,R5
	ADDC A,R5
	DA A
	MOV R5,A
	MOV A,R4
	ADDC A,R4
	DA A
	MOV R4,A
	DJNZ R7,LO30
	RET
	
PTDS: MOV R1,A
	ACALL PTDS1
	MOV A,R1
	SWAP A
PTDS1:ANL A,#0FH
	MOV @R0,A
	INC R0
	RET
	
SSEE:	SETB RS1
	MOV R5,#05H
SSE2:	MOV 30H,#20H
	MOV 31H,#7EH
	MOV R7,#06H
SSE1:	MOV R1,#21H
	MOV A,30H
	MOVX @R1,A
	MOV R0,31H
	MOV A,@R0
	MOV DPTR,#DDFF
	MOVC A,@A+DPTR
	MOV R1,#22H
	MOVX @R1,A
	MOV A,30H
	RR A
	MOV 30H,A
	DEC 31H
	MOV A,#0FFH
	MOVX  @R1,A
	DJNZ R7,SSE1
	DJNZ R5,SSE2
	CLR RS1
	RET
DDFF: 	DB 0C0H,0F9H,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H
	DB 88H,83H,0C6H,0A1H,86H,8EH,0FFH,0CH,89H,0DEH
	END