어셈블리어 질문

TITLE	CAL
PAGE	60,132
CURSOR	MACRO	VALUE1,VALUE2
	MOV	AH,02
	MOV	BH,00
	MOV	DH,VALUE1
	MOV	DL,VALUE2
	INT	10H
	ENDM
;----------------------------------------
PRINTMSG	MACRO	MESSAGE
	MOV	AH,09
	MOV	DX,OFFSET MESSAGE
	INT	21H
	ENDM
;----------------------------------------
INPUTOPR	MACRO	BUFFER
	MOV	AH,0AH
	MOV	DX,OFFSET BUFFER
	INT	21H
	ENDM
;----------------------------------------
INCWORD	MACRO	BUF_COUNT,BUF_AREA
	LOCAL	JMP1
	MOV	BX,OFFSET BUF_AREA
	CMP	BUF_COUNT,2
	JE	JMP1
	MOV	AH,[BX]
	MOV	[BX],BYTE PTR'0'
	MOV	[BX]+1,AH
	MOV	[BX]+2,BYTE PTR'$'
JMP1:	MOV	BUF_COUNT,2
	ENDM
 
CONVERT_HEX	MACRO	INDEX
	MOV	AH,BYTE PTR<ol>
</ol>
 
	MOV	AL,AH
	AND	AH,0FH
	MOV	CL,4
	SHR	AL,CL
	MOV	BL,AH
	MOV	BH,10
	MUL	BH
	ADD	AL,BL
	ENDM
 
STSEG	SEGMENT
	DB	64 DUP(?)
STSEG	ENDS
;-----------------------------------------
DTSEG	SEGMENT
MESSAGE1	DB	'INPUT A:$'	
MESSAGE3	DB	'INPUT B:$'	
MESSAGE4	DB	'THE ANSWER IS$'	
NEGATIVE	DB	'-$'
;-----------------------------------------
DATA_BUF1	LABEL	BYTE
MAX_SIZE1	DB	3
BUF_COUNT1	DB	?
BUF_AREA1	DB	3 DUP(0)
 
DATA_BUF2	LABEL	BYTE
MAX_SIZE2	DB	3
BUF_COUNT2	DB	?
BUF_AREA2	DB	3 DUP(0)
 
DATA_BCD1	DB	1 DUP(?)
DATA_BCD2	DB	1 DUP(?)
 
RESULT_BCD	DB	5 DUP(?)
RESULT_ASC	DB	10 DUP(?)
 
OPER	DB	00H
DTSEG	ENDS
;--------------------------------------------
CDSEG	SEGMENT
MAIN	PROC	FAR
	ASSUME	CS:CDSEG,DS:DTSEG,SS:STSEG
	MOV	AX,DTSEG
	MOV	DS,AX
	MOV	AX,0600H
	MOV	BH,07
	MOV	CX,0000
	MOV	DX,184FH
	INT	10H
 
	CURSOR	10,15
	PRINTMSG MESSAGE1
	INPUTOPR DATA_BUF1
	INCWORD	BUF_COUNT1,BUF_AREA1
 
	CURSOR	11,15
	PRINTMSG	MESSAGE3
	INPUTOPR	DATA_BUF2
	INCWORD	BUF_COUNT2,BUF_AREA2
 
	MOV	BX,OFFSET BUF_AREA1
	MOV	DI,OFFSET DATA_BCD1
	CALL	CONV_BCD
 
	MOV	BX,OFFSET BUF_AREA2
	MOV	DI,OFFSET DATA_BCD2
	CALL	CONV_BCD
;---------------------------------------------
SELECT1:	CALL	BCD_ADD
	MOV	SI,OFFSET RESULT_BCD
	MOV	DI,OFFSET RESULT_ASC
	MOV	CX,02
	CALL	CONV_ASC
	JMP	PRINTGO
 
SELECT2:	CALL	BCD_SUB
	MOV	SI,OFFSET RESULT_BCD
	MOV	DI,OFFSET RESULT_ASC
	MOV	CX,01
	CALL	CONV_ASC
	JMP	PRINTGO
 
SELECT3:	CALL	ASC_MUL
	JMP	PRINTGO
 
SELECT4:	CALL	ASC_DIV
	CURSOR	15,15
	JMP	PRINTGO
PRINTGO:	
	PRINTMSG	RESULT_ASC
	CURSOR	30,00
	MOV	AH,4CH
	INT	21H
MAIN	ENDP
 
;-------------------------------------------
ASC_DIV	PROC
	MOV	BX,OFFSET DATA_BCD1
	MOV	DI,OFFSET DATA_BCD2
	MOV	SI,OFFSET RESULT_ASC
 
	CONVERT_HEX	DI
	MOV	DX,AX
	MOV	BX,OFFSET DATA_BCD1
	CONVERT_HEX	BX
 
	SUB	AH,AH
	DIV	DL
 
	MOV	SI,OFFSET RESULT_ASC
	MOV	DL,AH
	MOV	CX,02
BACK2:	MOV	BL,10
	SUB	AH,AH
	DIV	BL
	MOV	[SI]+1,AH
	DEC	SI
	LOOP	BACK2
 
	MOV	SI,OFFSET RESULT_ASC+2
	MOV	AL,DL
	MOV	CX,02
BACK3:	MOV	BL,10
	SUB	AH,AH
	DIV	BL
	MOV	[SI]+1,AH
	DEC	SI
	LOOP	BACK3
	MOV	SI,OFFSET RESULT_ASC
	OR	WORD PTR[SI],3030H
	INC	SI
	INC	SI
	OR	WORD PTR[SI],3030H
	INC	SI
	INC	SI
	MOV	[SI],BYTE PTR'$'
	RET
ASC_DIV	ENDP
 
ASC_MUL	PROC
	MOV	BX,OFFSET DATA_BCD1
	MOV	DI,OFFSET DATA_BCD2
	MOV	SI,OFFSET RESULT_ASC
 
	CONVERT_HEX	BX
	MOV	DL,AL
	CONVERT_HEX	DI
 
	MUL	DL
	MOV	CX,04
 
BACK1:	SUB	DX,DX
	MOV	BX,000AH
	DIV	BX
	MOV	[SI]+3,DL
	DEC	SI
	LOOP	BACK1
 
	MOV	SI,OFFSET RESULT_ASC
	OR	WORD PTR[SI],3030H
	INC	SI
	INC	SI
	OR 	WORD PTR[SI],3030H
	INC	SI
	INC	SI
	MOV	[SI],BYTE PTR'$'
	RET
ASC_MUL	ENDP
;--------------------------------------
BCD_ADD	PROC
	MOV	BX,OFFSET DATA_BCD1
	MOV	DI,OFFSET DATA_BCD2
	MOV 	SI,OFFSET RESULT_BCD
	CLC
	MOV	AL,[BX]	
	ADC	AL,[DI]
	DAA
	MOV	[SI]+1,AL
	ADC	BYTE PTR[SI],00
	RET	
BCD_ADD	ENDP
;--------------------------------------
BCD_SUB	PROC
	MOV	BX,OFFSET DATA_BCD1
	MOV	DI,OFFSET DATA_BCD2
	MOV	SI,OFFSET RESULT_BCD
	CLC
	MOV	AL,[BX]
	SBB	AL,[DI]
	DAS
	MOV	[SI],AL
	MOV	AL,[BX]
	CMP	AL,[DI]
	JAE	JMP4
	CURSOR	14,29
	PRINTMSG	NEGATIVE
	MOV	DH,99H
	SUB	DH,[SI]
	MOV	DH,99H
	SUB	DH,[SI]
	MOV	[SI],DH
	INC	BYTE PTR[SI]
JMP4:	RET
BCD_SUB	ENDP
;-------------------------------------
CONV_BCD	PROC
AGAIN1:	MOV	AX,[BX]
	XCHG	AH,AL
	AND	AX,0F0FH
	MOV	CL,4
	SHL	AH,CL
	OR	AL,AH
	MOV	[DI],AL
	RET
CONV_BCD	ENDP
;-------------------------------------
CONV_ASC	PROC
AGAIN2:	MOV	AL,[SI]
	MOV	AH,AL
	AND	AX,0F00FH
	PUSH	CX
	MOV	CL,04
	SHR	AH,CL
	OR	AX,3030H
	XCHG	AH,AL
	MOV	[DI],AX
	INC	SI
	ADD	DI,2
	POP	CX
	LOOP	AGAIN2
	MOV	[DI],BYTE PTR'$'
	RET
CONV_ASC	ENDP
;-------------------------------------
CDSEG	ENDS	
END	MAIN