Re: How the hard-disk is memory mapped???
- From: onderyazar@xxxxxxxxx
- Date: Wed, 11 Mar 2009 10:48:55 -0700 (PDT)
Hi Nagarjuna,
To start with the the whole Hard disk is not memory mapped but its
controller is. The controller has an access window and probably a
buffer area in that window that the data from hard disk is copied to/
from. It's drivers responsibility to convert application requests to
Disk controller commands (such as sector erase / read write) and copy
buffers from HDD Contoller memory space to the real memory space when
requested..
Hope this helps..
Onder
On Mar 9, 9:47 am, e.nagarjunare...@xxxxxxxxx wrote:
Hi,
On a 32-bit architecture, the maximum physical address space we can
have is 4GB.
All the peripheral devices, physical memory(RAM), and storage etc. is
mapped in the
available 4GB space.
Doubt: How we are able to access 160GB, 320GB hard-disk content ??
If only status, control registers of hard-disk drive are memory
mapped, then how the
processor able to access different sectors and tracks from hard
disk???
I have only vague picture. Please can anybody explain me this ?
Thanks in advance
Regards
Nagarjuna.
.
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- How the hard-disk is memory mapped???
- From: e . nagarjunareddy
- How the hard-disk is memory mapped???
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