a4-3.asm

来自「一些微机接口的例子」· 汇编 代码 · 共 91 行

;A4-3.asm
;乘法运算

STACK1  SEGMENT STACK
         DW 256 DUP(?)
STACK1  ENDS

DATA 	SEGMENT
MES1    DB 'The result is:$'
ERRMES  DB 'Error exist!$'
DATA1 	DB 00H,02H,03H,04H,05H
DATA2 	DB 03H
RESULT	DB 06H DUP(0)
DATA ENDS
	
CODE SEGMENT
	ASSUME CS:CODE,DS:DATA
	
START: MOV 	AX,DATA
	   MOV 	DS,AX

	   MOV 	SI,OFFSET DATA2
	   MOV 	BL,[SI]
	   AND 	BL,0FH
	   CMP 	BL,09H
	   JNC 	ERROR
	
	   MOV 	SI,OFFSET DATA1
	   MOV 	DI,OFFSET RESULT
	   MOV 	CX,0005H
A1:	   MOV 	AL,[SI+04H]
	   AND 	AL,0FH
	   CMP 	AL,09H
	   JNC 	ERROR
	   DEC 	SI
	   MUL 	BL
	   AAM
	   ADD 	AL,[DI+05H]
	   AAA
	   MOV 	[DI+05H],AL
	   DEC 	DI
	   MOV 	[DI+05H],AH
	   LOOP 	A1

	   MOV	DX,OFFSET MES1
	   MOV	AH,09H
	   INT	21H
	   MOV 	CX,06H
	   MOV 	SI,OFFSET RESULT
A2:	   CALL	SHOW
	   MOV	DL,20H
	   MOV	AH,02H
	   INT	21H
	   INC	SI
	   LOOP	A2

	   MOV	AX,4C00H
	   INT	21H

ERROR: MOV	DX,OFFSET ERRMES
	   MOV	AH,09H
	   INT	21H
	   MOV	AX,4C00H
	   INT	21H

SHOW	PROC	NEAR
	   MOV	AL,DS:[SI]
	   AND	AL,0F0H			;取高4位
	   SHR	AL,4
	   CMP	AL,0AH			;是否是A以上的数
	   JB	C2		
	   ADD	AL,07H		
C2:	   ADD	AL,30H		
	   MOV	DL,AL			;show character 
	   MOV	AH,02H
	   INT	21H
	   MOV	AL,DS:[SI]
	   AND	AL,0FH			;取低4位
	   CMP	AL,0AH
	   JB	C3
	   ADD 	AL,07H
C3:	   ADD	AL,30H
	   MOV	DL,AL			;show character 
	   MOV	AH,02H
	   INT	21H
	   RET
	   ENDP	
	
CODE  ENDS
	   END	START