Re: 80x86 Assembly

[Tal Achituv]

[EMAIL PROTECTED] wrote:
Quoting Tal Achituv <[EMAIL PROTECTED]>:
NOP and XCHG ax,ax are the same commands.
 

This is true, this is why I said "which is not the trivial AX,AX excahnge",
In the Intel Pentium op-code reference they mention something called 
"0x90/rw XCHG AX,addr16" or something like that, which contradicts my 
assumption that 0x90 is NOP and cannot be anything other than nop.

So basically - my question is - Is that a typo - or is my assumption wrong?
Hi!
I've recently found (in an Intel book) that the opcode 0x90 could be a
prefix for XCHG command
which is not the trivial AX,AX excahnge.
afaik 0x90 can be only NOP.
Is there any other explanation other than a typo?
(some come to mind - such as various conditions that I might be
neglecting - like the cpu mode and so on)
Tal.
=================================================================
To unsubscribe, send mail to [EMAIL PROTECTED] with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail [EMAIL PROTECTED]
   

=================================================================
To unsubscribe, send mail to [EMAIL PROTECTED] with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail [EMAIL PROTECTED]
 


=================================================================
To unsubscribe, send mail to [EMAIL PROTECTED] with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail [EMAIL PROTECTED]