ceshi.asm

键盘与显示类程序

	MOV R7,#2H
	MOV R0,#30H
	MOV R1,#40H
	MOV A,#11
	MOV @R0,A
	INC R0
	MOV A,#11
	MOV @R0,A
	MOV A,#22
	MOV @R1,A
	INC R1
	MOV @R1,A
	ACALL BCDA
	ACALL DISP


BCDA: MOV A,R7 ;取字节数至R2中
	MOV R2,A
	ADD A,R0 ;初始化数据指针
	MOV R0,A
	MOV A,R2
	ADD A,R1
	MOV R1,A
	CLR C
BCD1: DEC R0 ;调整数据指针
	DEC R1
	MOV A,@R0
	ADDC A,@R1 ;按字节相加
	DA A ;十进制调整
	MOV @R0,A ;和存回[R0]中
	DJNZ R2,BCD1 ;处理完所有字节
	RET
	
	
DISP:MOV A,31H
	ANL A,#0F0H
	SWAP A
	MOV 75H,A
	MOV A,31H
	ANL A,#0FH
	MOV 74H,A
	
	MOV A,30H
	ANL A,#0F0H
	SWAP A
	MOV 77H,A
	MOV A,30H
	ANL A,#0FH
	MOV 76H,A
	
DISP_1:	MOV DPTR,#0FF82H
	MOV A,#90H
	MOVX @DPTR,A
	MOV R0,#70H
	MOV R7,#04H
	MOV DPTR,#0FF81H
DL0:	MOV A,@R0
	ADD A,#17H
	MOVC A,@A+PC
	
	PUSH ACC
	MOV A,R0
	JB ACC.0,NEXT
	ANL A,#0FH         ;去掉最后一位的小数点
	JZ NEXT  
	POP ACC
	ORL A,#80H
	AJMP NEXT0
NEXT:	POP ACC

NEXT0:	MOVX @DPTR,A 
	INC R0
	DJNZ R7,DL0
	RET
TAB:	DB 3FH,06H,5BH,4FH,66H
	DB 6DH,7DH,07H,7FH,6FH
	END