用7ch中斷例程完成jmp near ptr s指令的功能,用bx向中斷例程傳送轉移位移。
阿新 • • 發佈:2018-11-12
應用舉例:在螢幕的第12行,顯示data段中以0結尾的字串。
assume cs:code data segment db 'conversation',0 data ends code segment start: mov ax, data mov ds, ax mov si, 0 mov ax, 0b800h mov es, ax mov di, 12*160 s: cmpbyte ptr [si], 0 je ok mov al, [si] mov es:[di], al inc si add di, 2 mov bx, offset s-offset ok int 7ch ok: mov ax, 4c00h int 21h code ends end start
安裝程式
assume cs:code code segment start: mov ax, cs mov ds,ax mov si,offset do0 mov ax,0 mov es,ax mov di,200h mov cx,offset do0end-offsetdo0 cld rep movsb mov ax,0 mov es,ax mov word ptr es:[7ch*4],200h mov word ptr es:[7ch*4+2],0 mov ax,4c00h int 21h do0: push bp mov bp,sp add [bp+2],bx pop bp iret mov ax,4c00h int 21h do0end: nop code ends end start