小鸟飞过.txt

用小写字母v变为破折号来模仿飞鸟的动作。调用BIOS的字符显示功能 10H

DATA         SEGMENT
             WIN_ULC   EQU 30           ;窗口起始列
             WIN_ULR   EQU 8            ;窗口起始行
             WIN_WIDTH DB  10           ;飞行宽度
DATA ENDS
CODE         SEGMENT
             ASSUME CS:CODE,DS:DATA     ;指定段寄存器
START:       MOV AX,DATA
             MOV DS,AX
             CALL CLEAR_SCREEN          ;清屏
             MOV DH,WIN_ULR
             MOV DL,WIN_ULC
FLY:         MOV AH,02H                 ;设置光标位置（窗口左上角）
             MOV BH,0
             INT 10H
             MOV CX,1                   ;显示一个‘v’
             MOV AL,'v'
             MOV BL,07H
             MOV AH,09H
             MOV BH,0
             INT 10H
             INC DL                     ;列坐标加一
             MOV AH,02H                 ;设置光标位置
             MOV BH,0
             INT 10H
             MOV CX,1                   ;显示破折号
             MOV AL,'_'
             MOV BL,07H
             MOV AH,09H
             MOV BH,0
             INT 10H
             INC DH                     ;行坐标加一
             MOV CX,65535
             CALL WAIT1                 ;暂停
             CALL CLEAR_SCREEN          ;清屏
             DEC WIN_WIDTH
             JZ  EXIT
             JMP FLY
CLEAR_SCREEN PROC NEAR                  ;清屏子程序
             PUSH AX
             PUSH BX
             PUSH CX
             PUSH DX
             MOV AH,6
             MOV AL,0
             MOV BH,0
             MOV CH,0
             MOV CL,0
             MOV DH,24
             MOV DL,79
             INT 10H
             MOV DH,0
             MOV DL,0
             MOV AH,2   
             INT 10H
             POP DX
             POP CX
             POP BX
             POP AX
             RET
CLEAR_SCREEN ENDP
WAIT1        PROC NEAR
             PUSH AX
WAIT2:
             IN AL,61H
             AND AL,30H
             CMP AL,AH
             JE WAIT2
             MOV AH,AL
             LOOP WAIT2
             POP AX
             RET
WAIT1        ENDP
EXIT:        MOV AX,4C00H
             INT 21H
CODE         ENDS
             END START