练习一：统计复数的个数
DTSEG SEGMENT
MES1 DB 'The result is:$'
NUMB DB 12H,88H,82H,89H,33H,90H,01H,10H,0BDH,01H
DTSEG ENDS
CDSEG SEGMENT
ASSUME CS:CDSEG,DS:DTSEG
START:MOV AX,DTSEG
MOV DS,AX
MOV DX,OFFSET MES1
MOV AH,09H
INT 21H
MOV BL,0H
MOV CX,0AH
MOV SI,OFFSET NUMB
NEXT: MOV AX,[SI]
AND AX,80H ；判断是否是负数
CMP AX,0H
JG MIN
JMP CON
MIN: INC BL
CON: INC SI
LOOP NEXT
CALL SHOW
MOV AH,4CH
INT 21H
SHOW PROC NEAR
PUSH AX
PUSH DX
MOV AL,BL
AND AL,0F0H ;取高4位
SHR AL,4
CMP AL,0AH ;是否是A以上的数
JB C2
ADD AL,07H
C2: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
MOV AL,BL
AND AL,0FH ;取低4位
CMP AL,0AH
JB C3
ADD AL,07H
C3: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
POP DX
POP AX
RET
ENDP
CDSEG ENDS
END START
联系2：找出最大最小值
; You may customize this and other start-up templates;
; The location of this template is c:\emu8086\inc\0_com_template.txt
STACK1 SEGMENT STACK
DW 256 DUP(?)
STACK1 ENDS
DDATA SEGMENT
MES1 DB 'The least number is:$'
MES2 DB 0AH,0DH,'The largest number is:$'
NUMB DB 0D9H,07H,8BH,0C5H,0EBH,04H,9DH,0F9H
DDATA ENDS
CODE SEGMENT
ASSUME CS:CODE,DS:DDATA
START: MOV AX,DDATA
MOV DS,AX
MOV SI,OFFSET NUMB
MOV CX,0008H
;JCXZ A4
MOV BH,[SI]
MOV BL,BH ；BL记录最小值，BH记录最大值
A1: LODSB ;AL=DS:[SI],SI=SI+1 取串指令
CMP AL,BH
JBE A2
MOV BH,AL
JMP A3
A2: CMP AL,BL
JAE A3
MOV BL,AL
A3: LOOP A1
A4: MOV DX,OFFSET MES1 ;show mes1
MOV AH,09H
INT 21H
MOV AL,BL ;show the least number
AND AL,0F0H ;get the highest 4 bits
SHR AL,4
CMP AL,0AH
JB C2
ADD AL,07H
C2: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
MOV AL,BL
AND AL,0FH ;get the lowest 4 bits
CMP AL,0AH
JB C3
ADD AL,07H
C3: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
MOV DX,OFFSET MES2 ;show mes2
MOV AH,09H
INT 21H
MOV AL,BH ;show the largest number
AND AL,0F0H ;get the highest 4 bits
SHR AL,4
CMP AL,0AH
JB C22
ADD AL,07H
C22: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
MOV AL,BH
AND AL,0FH ;get the lowest 4 bits
CMP AL,0AH
JB C33
ADD AL,07H
C33: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
MOV AX,4C00H ;go back to dos
INT 21H
CODE ENDS
END START
练习3：双精度加法计算
要求计算X+Y=Z，将结果Z输出到屏幕上，其中X=001565A0H，Y=0021B79EH。实验利用累加器AX,先求低十六位和，并存入地址存储单元，后求高16位和，再存入高址存储单元。由于地位可能向高位有进位，因而高位相加语句需用ADC指令，则地位相加有进位时，CF=1，高位字相加时，同时加上CF中的1。在80386以上微机中可以直接使用32位寄存器和32位加法指令完成。
;二进制双精度加法运算
STACK1 SEGMENT STACK
DW 256 DUP(?)
STACK1 ENDS
DATA SEGMENT
MES1 DB 'The result is:$'
XL DW 65A0H
XH DW 0015H
YL DW 0B79EH
YH DW 0021H
DATA ENDS
CODE SEGMENT
ASSUME CS:CODE,DS:DATA
START: MOV AX,DATA
MOV DS,AX
MOV DX,OFFSET MES1 ;将MES1偏移地址给DX
MOV AH,09H ;将MES1中的内容输出到屏幕
INT 21H
MOV AX,XL
ADD AX,YL
MOV BX,AX
MOV AX,XH
ADC AX,YH
PUSH BX ;入栈保存BX
CALL SHWORD ;先去执行SHWORD
POP BX ;返回继续执行BX出栈处理
MOV AX,BX ;此时AX中是低16位之和
CALL SHWORD ;再次调用SHWORD
MOV AX,4C00H
INT 21H
SHWORD PROC NEAR
MOV BL,AH ;保持高16位的高8位
CALL SHOW ;显示结果
MOV BL,AL ;保持高16位的低8位
CALL SHOW ;显示结果
RET
ENDP
SHOW PROC NEAR
PUSH AX ;保持AX
PUSH DX ;保存DX
MOV AL,BL
AND AL,0F0H ;AL与0F0H相与取高4位
SHR AL,4
CMP AL,0AH ;是否是A以上的数
JB C2
ADD AL,07H ;A以上的数加07H折显示的是字母
C2: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
MOV AL,BL
AND AL,0FH ;AL与0FH相与取低4位
CMP AL,0AH
JB C3
ADD AL,07H
C3: ADD AL,30H
MOV DL,AL ;show character
MOV AH,02H
INT 21H
POP DX
POP AX
RET
ENDP
CODE ENDS
END START