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RE: I/O mapped i/o

  
sir,
In memory mapped I/O I/O address space is allocated in main memory.
Where the memory is allocated for i/o in I/O mapped I/O.

Hoping a prompt reply,
Nawaz.

Hi,
If you are talking about i386, Then, there is a seperate I/O space for I/O mapped I/O. It is completely different from Address space. I/O space is 64K in pentiums (IIRC).
so, I/O space is not in memory. So, it cannot be accessed by memory transfer instructions like mov, inc etc. They can be only accessed by in, out, ins and outs instructions.

Regards manish

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