12_2.asm

汇编写的非压缩BCD码减法。实现两个非压缩BCD码在机器语言中的减法。但未实现输入

DATA SEGMENT
	A DB 07H, 03H, 06H, 02H, 01H
	B DB 00H, 04H, 02H, 00H, 03H
DATA ENDS

CODE SEGMENT
	ASSUME CS:CODE, DS:DATA
START:	MOV AX, DATA
	MOV DS, AX
	LEA SI, A
	LEA DI, B 
	MOV CX, 5
	CLC
L0:	MOV AL, [SI+4]
	SBB AL, [DI+4]
	AAS
	MOV [SI+4], AL
	DEC SI
	DEC DI
	DEC CX
	JNZ L0
	LEA SI,A
	MOV CX, 5
L1:	MOV DL, [SI]
	ADD DL, 30H
	MOV AH, 02H
	INT 21H
	INC SI
	DEC CX
	JNZ L1
	MOV AH, 4CH
	INT 21H
CODE ENDS
END START