Writing a 2-byte value into [ffff]

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l4m2

Joined: 15 Jan 2015
Posts: 674

l4m2 17 Oct 2015, 11:14

I used Proteus to run it:(you should turn it into real code if you want to try it

Code:

mov [f001:ffff], ffff  ;[0000F]=[00010]=FF
mov [f000:ffff], ffff  ;halt
mov [0000:ffff], ffff  ;[0FFFF]=[10000]=FF

(not sure whether it stimulates right as a real one)
But for a newer cpu, it causes a #GP (right?) which will be regarded as IRQ5. after IRET the running will go into a mess.
Are what i said right?

17 Oct 2015, 11:14

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20522
Location: In your JS exploiting you and your system

revolution 17 Oct 2015, 13:24

You didn't supply enough information to answer your question.

What mode is the CPU in?

What are the values of the segment register shadow registers?

What is in the paging tables?

Is the A20 gate enabled?

17 Oct 2015, 13:24

l4m2

Joined: 15 Jan 2015
Posts: 674

l4m2 19 Oct 2015, 15:14

8086 in proteus

19 Oct 2015, 15:14

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