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fat32

Posted: Wed Aug 29, 2007 9:17 pm
by xyjamepa
Hi...

I want to know if I can implement FAT32 on my 1.44MB floppy,
Right now I'm not planning to switch to H.D.D
Also I don't want to implement fat12 or any other file system,
And if we are talking about the huge waste of space It's not
a problem right now .
So can I do that?


Thanx.

Posted: Wed Aug 29, 2007 9:29 pm
by Zenith
The short answer is: no.

The minimum size for a FAT32 partition is 512MB. (And even then, formatting w/ FAT16 would be much better)

Hope this helps!

Posted: Thu Aug 30, 2007 9:53 am
by Combuster
The long answer:

When parsing a FAT partition, one must look at the amount of clusters contained within that partition. if the amount of clusters fits within the 12 bits, the partition is FAT12. If the cluster count does not fit in 12 bits, but it does in 16 bits, its FAT16. When you have more clusters, it automatically becomes FAT32. The signature string (which would logically be used for such things) was never checked by microsoft so we can't force the use of a certain variant without breaking compatibility.

You can forcibly format a medium with the required amount of bits, but it'll potentially break as soon as you try to feed it to a driver which expects a different amount of bits. Hence, don't try it under windows. AFAIK linux allows you to do a manual override, if you are serious.

The short answer:
Not worth the trouble.

Posted: Thu Aug 30, 2007 10:40 am
by Smilediver
karekare0 wrote:The short answer is: no.

The minimum size for a FAT32 partition is 512MB. (And even then, formatting w/ FAT16 would be much better)

Hope this helps!
Actually minimum size should be 32 MiB if you use 1 block clusters.

Posted: Thu Aug 30, 2007 7:17 pm
by xyjamepa
Hi...

Okay ...but now I'm a littel confused,
I think must of you heared of MenuetOS or even try it,
any way, this os supports FAT32 on 1.44MB floppy.
Could you please tell me how can they do that?
Or how did that happen?

Thanx.

Posted: Thu Aug 30, 2007 9:40 pm
by Dex
abuashraf wrote:Hi...

Okay ...but now I'm a littel confused,
I think must of you heared of MenuetOS or even try it,
any way, this os supports FAT32 on 1.44MB floppy.
Could you please tell me how can they do that?
Or how did that happen?

Thanx.
If you want a OS other than yours, to read/write than you can not use fat32 on a floppy.
You can mod your own ver to readwrite using fat32 to and from floppy, you will also need to make your own formating tools.
But you would get errors or corruption if you tried to use it in windows etc.

PS: MenuetOS supports FAT32 on 1.44MB floppy, i think you may be wrong, where did you read this ?.

Posted: Fri Aug 31, 2007 1:11 am
by Smilediver
abuashraf wrote:Hi...

Okay ...but now I'm a littel confused,
I think must of you heared of MenuetOS or even try it,
any way, this os supports FAT32 on 1.44MB floppy.
Could you please tell me how can they do that?
Or how did that happen?

Thanx.
This is taken from Microsoft's fat32 specifications doc:

Code: Select all

FAT Type Determination
There is considerable confusion over exactly how this works, which leads to many “off by 1â€

Posted: Fri Aug 31, 2007 7:28 pm
by xyjamepa
Hi...

okay guys let's say this in another way...
I want to read and write files to 1.44MB floppy from my os,
also when I open my os image using VFD,from my xp which uses FAT32
as a file system ,I want be able to read this files and changing them add/delete
so after that when I boot usign this image I can see this files changed.
I hope you understand what I'm tring to say.May be you don't
down to my bad explain so here's another one:
Let's assume I made a file from my os and played a little bit with it,
now I got back to my win xp which uses FAT32 as file system,
here inside xp if I open my os image I want to see the file I made,
and read it...that's all.

so the question is how am I suppose to do that if I can't implement
FAT32 on a 1.44MB floppy?

Thanx.

Posted: Fri Aug 31, 2007 7:37 pm
by frank
I'm sure that any tool that will read and write 32 bit FAT images will also read and write to 12 and 16 bit images. Just stick to 12 bit with floppies. It will be a lot easier that way, maybe not to program for (12 bit is hard :)), but still easier. Unless you don't want compatibility, then you can do whatever you want.

Posted: Sat Sep 01, 2007 12:17 pm
by xyjamepa
Hi...

@Frank:I tested a floppy image of your os and I found exactly what I want..
so would you please tell me what kind of file system did you implement to work on 1.44 floppy?
here I'm talking about version 0.3.1

@Dex:if MenuetOS doesn't support FAT32 on 1.44MB floppy,
Do you know what kind of file system does it support on 1.44MB floppy?

Thanx.

Posted: Sat Sep 01, 2007 12:21 pm
by frank
abuashraf wrote:Hi...

@Frank:I tested a floppy image of your os and I found exactly what I want..
so would you please tell me what kind of file system did you implement to work on 1.44 floppy?
here I'm talking about version 0.3.1
Thanx.
For my OS I use 12 bit FAT.

There are different "versions" of FAT depending on the size of the disk that it is on. The three different versions are 12 bit, 16 bit, and 32 bit. There are only minor differences between the different versions.

Posted: Sat Sep 01, 2007 12:42 pm
by inflater
@Dex:if MenuetOS doesn't support FAT32 on 1.44MB floppy,
Do you know what kind of file system does it support on 1.44MB floppy?
FAT12 of course ;) And for harddisks, FAT32 in "experimental stage" (i've saw in the 32bit version of setup program: Test FAT32 functions with extreme care). :)

Why would you use FAT32 for floppies?

Regards
inflater

Posted: Sat Sep 01, 2007 1:10 pm
by Dex
Now remember i have not used menuetos in a number of years, but as you can read/write to a menuet floppy in windows its FAT12, also menuet loads the whole floppy image from the floppy in to memory, and users it as a ram disk.

You maybe thinking in terms of ramdisk ?
Here's a simple example:
http://download.dezfoul.net/dos/program ... AMDISK.ASM

Posted: Sun Sep 02, 2007 2:34 pm
by xyjamepa
Thank you guys ...I'm okay now. 8)