Machine language

From ThorstensHome
Revision as of 12:14, 14 December 2014 by ThorstenStaerk (Talk | contribs)

Jump to: navigation, search

This shows a mapping of x86 machine language to assembler


00 01                 add    BYTE PTR [bx+di],al
00 41 41              add    BYTE PTR [bx+di+0x41],al
00 ff                 add    bh,bh 
0a                    .byte 0xa 
40                    inc    ax 
41                    inc    cx 
42                    inc    dx 
43                    inc    bx 
44                    inc    sp 
45                    inc    bp 
46                    inc    si 
47                    inc    di 
48                    dec    ax 
49                    dec    cx 
4a                    dec    dx 
4b                    dec    bx 
4c                    dec    sp 
4d                    dec    bp
4e                    dec    si 
4f                    dec    di 
50                    push   ax
51                    push   cx
52                    push   dx
53                    push   bx
54                    push   rsp 
85 c0                 test ax,ax  
90                    NOP 
b8 00 00 00 00        mov    eax,0x0 
c3                    ret  
cd 10                 int 10 
eb fd                 short                          jump to executing the byte before eb 
fa                    cli                            This will clear the interrupt flag in the processor meaning interrupts will not be processed after the flag is set again. This means a high risk - no more keyboard input etc.. So this is a privileged command and may only be executed by the operating system.