小镇的夕阳|修改硬盘MBR代码,用1024字节实现一个操作系统启动管理器( 二 )


:06A5 B700 MOV BH,00
:06A7 CD10 INT 10
:06A9 BE9009 MOV SI,0990
:06AC B004 MOV AL,04
:06AE A28307 MOV [0783],AL
:06B1 E86200 CALL 0716
:06B4 EB88 JMP 063E
:06D0 A08107 MOV AL,[0781]
:06D3 3A068007 CMP AL,[0780]
:06D7 7606 JBE 06DF
:06D9 B001 MOV AL,01
:06DB A28107 MOV [0781],AL
:06DE C3 RET
:06DF 0401 ADD AL,01#第2行
:06E1 88C6 MOV DH,AL
:06E3 B220 MOV DL,20
:06E5 B402 MOV AH,02
:06E7 B700 MOV BH,00
:06E9 CD10 INT 10
:06EB A08107 MOV AL,[0781]
:06EE 3A068207 CMP AL,[0782]
:06F2 7504 JNZ 06F8
:06F4 B305 MOV BL,05
:06F6 EB02 JMP 06FA
:06F8 B308 MOV BL,08
:06FA 881E8307 MOV [0783],BL
:06FE FEC8 DEC AL
:0700 B110 MOV CL,10
:0702 F6E1 MUL CL
:0704 059007 ADD AX,0790
:0707 89C6 MOV SI,AX
:0709 E80A00 CALL 0716
:070C A08107 MOV AL,[0781]
:070F FEC0 INC AL
:0711 A28107 MOV [0781],AL
:0714 EBBA JMP 06D0
:0716 AC LODSB
:0717 3C00 CMP AL,00
:0719 740A JZ 0725
:071B B40E MOV AH,0E
:071D 8A1E8307 MOV BL,[0783]
:0721 CD10 INT 10
:0723 EBF1 JMP 0716
:0725 C3 RET
小镇的夕阳|修改硬盘MBR代码,用1024字节实现一个操作系统启动管理器


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