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edfed



Joined: 20 Feb 2006
Posts: 4324
Location: Now
edfed 18 Oct 2006, 10:48
why do we need a ramdisk?

because it is a memory model who can be structured

Soooo.... if all the system is based on a ramdisk,you can easily integrate the Hard Disks and the I/O ports in its structure

For the moment i work only in the real mode of the µP, the segmentation problem is a solution with ramdisk

a sector is 512bytes leng, a segment is 64kbytes leng and the interstice beetwen to segments is 16 bytes

to access a sector (whitout dos INT), you must specify a CHS or LBA parameter
and then transfert the sector in the destination segment

and after you must perform a translation to exploit the file if it's a File System folder.

but when you load a folder in the ram, it's occupies a memory place and is not necessaryly erased after use and can be already in memory before reloading

The goal of this thead is to find a manner to integrate the virtual RAM (DDR,DRAM ...) into the file system and then get more speed and more stability and flexibility

the basis of the system is a field of flags indicates the state of a unit of memory, the sector (512b), therefore, a real address mode segment contains 128 sectors

we need one sector to manage 504*8=4032 sectors
the 12 rest bytes are used to indicate the size of the valid data, the next sector in the field and the numbers of used sectors in the cluster (here, one cluster is 4032 sectors)

field:
size dd ?
used dd ?
flags array
......
......
next sector dd ?

a sector is identified by its CHS or LBA parameters, so we put the parameter in the Virtual LBA form and store it in a Dword

SEE YOU AGAIN FOR THE NEXT TIME
Post 18 Oct 2006, 10:48
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vid
Verbosity in development


Joined: 05 Sep 2003
Posts: 7105
Location: Slovakia
vid 18 Oct 2006, 19:48
moving to main... no idea where it belongs, but surely not projects.

by the way, your 3 code blocks at end seems too "transparent"
Post 18 Oct 2006, 19:48
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edfed



Joined: 20 Feb 2006
Posts: 4324
Location: Now
edfed 24 Oct 2006, 10:49
i don't know what they do there
but it's not a problem
Post 24 Oct 2006, 10:49
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sylwek32



Joined: 27 Apr 2006
Posts: 339
sylwek32 24 Oct 2006, 12:23
Post 24 Oct 2006, 12:23
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