6-9.asm

将存于DAT1开始的1个8字节BCD相加,结果放在SUM.考虑溢出.

;将存于DAT1开始的1个8字节BCD相加,结果放在SUM.考虑溢出.
DATA        SEGMENT
       DAT1  DB  1,2,3,4,5,6,7,8
      SUM   DW  ? ,?
DATA        ENDS

STACK      SEGMENT
  ST1      DB    100  DUP(?)
  TP       EQU   LENGTH ST1
STACK      ENDS 
     
CODE        SEGMENT
ASSUME   CS:CODE,   DS:DATA,   SS:STACK

 START:    MOV     AX, DATA
           MOV     DS, AX
           MOV     AX, STACK
           MOV     SS, AX           ;初始化堆栈段
           MOV     CX,8            ;循环次数 CX=8
           MOV     SI,OFFSET  DAT1
           MOV     CX,8 
           MOV     AL,[SI]
           CLC
           MOV     AH,0
        DO:INC     SI
           ADD     AL,[SI]
           AAA
           JNC      LP    
           INC     AH  
           CLC
     LP:   DEC     CX
           JNZ     DO
           MOV     SUM,AX
           OR     AH,30H
           MOV    DL,AH
           MOV    AH,02H
           INT    21H
           MOV    AX,4C00H
           INT     21H 

CODE       ENDS
           END     START