a5.asm

一些微机接口的例子

;A5.asm
;分支程序设计实验

STACK1  SEGMENT STACK
         DW 256 DUP(?)
STACK1  ENDS

DDATA	SEGMENT
MES1	DB 'The least   number is:$'
MES2 	DB 0AH,0DH,'The largest number is:$'
NUMB	DB 0D9H,07H,8BH,0C5H,0EBH,04H,9DH,0F9H
DDATA	ENDS

CODE SEGMENT
	ASSUME CS:CODE,DS:DDATA
	
START: MOV	AX,DDATA
	   MOV	DS,AX

	   MOV 	SI,OFFSET NUMB
	   MOV 	CX,0008H
	   JCXZ A4
	   MOV 	BH,[SI]
	   MOV 	BL,BH
A1:	   LODSB			;AL=DS:[SI],SI=SI+1
	   CMP 	AL,BH
	   JBE 	A2
	   MOV 	BH,AL
	   JMP 	A3
A2:	   CMP 	AL,BL
	   JAE 	A3
	   MOV 	BL,AL
A3:	   LOOP A1

A4:	   MOV	DX,OFFSET MES1	;show mes1
	   MOV	AH,09H		
	   INT 	21H	

	   MOV	AL,BL		;show the least number
	   AND	AL,0F0H		;get the highest 4 bits
	   SHR	AL,4
	   CMP	AL,0AH		
	   JB	C2		
	   ADD	AL,07H		
C2:	   ADD	AL,30H		
	   MOV	DL,AL		;show character 
	   MOV	AH,02H
	   INT	21H
	   MOV	AL,BL
	   AND	AL,0FH		;get the lowest 4 bits
	   CMP	AL,0AH
	   JB	C3
	   ADD 	AL,07H
C3:	   ADD	AL,30H
	   MOV	DL,AL		;show character 
	   MOV	AH,02H
	   INT	21H

	   MOV	DX,OFFSET MES2	;show mes2
	   MOV	AH,09H		
	   INT 	21H	

	   MOV	AL,BH		;show the largest number
	   AND	AL,0F0H		;get the highest 4 bits
	   SHR	AL,4
	   CMP	AL,0AH		
	   JB	C22		
	   ADD	AL,07H		
C22:   ADD	AL,30H		
	   MOV	DL,AL		;show character 
	   MOV	AH,02H
	   INT	21H
	   MOV	AL,BH
	   AND	AL,0FH		;get the lowest 4 bits
	   CMP	AL,0AH
	   JB	C33
	   ADD 	AL,07H
C33:   ADD	AL,30H
	   MOV	DL,AL		;show character 
	   MOV	AH,02H
	   INT	21H

	   MOV	AX,4C00H	;go back to dos
	   INT	21H
CODE ENDS
       END START