Re: X-IDE and Power Cartridge
Date: 2007-12-28 11:44:29

On 2007-12-28, at 01:43, Jim Brain wrote:

>> P.S. A different subject - I don't know why but it seems to me  
>> that nobody likes the idea of (re)using IDE64 partition scheme and  
>> filesystem.. I wonder why..?
> We are defitely using the IDE64 Partition Scheme, as it uses the  
> std IBM IDE partition scheme.
> If we implement the IDE64 FS, we should absolutely use partition  
> type 0xcf (the one they use).

Well - the word "absolutely" doesn't fit IMHO. IDEDOS is still being  
developed and I don't think it would be impossible to persuade the  
author(s) with reasonable arguments to change what is used there - if  
that is needed for some reasons.

>   Note, though, there might be issues using 0xcf for other FS- 
> types.  For one, IDE64 will no doubt assume an 0xcf partition type  
> is IDEDOS FS, but if we overload that partition type with other FS  
> layouts (like Linux uses 0x83 for multiple FStypes - xiafs, ext2,  
> ext3, reiserfs, etc.), and someone tries to share a CF or IDE drive  
> between the two adapters, major issues and data lossage will occur.

See above. Also:
a) partition type does not necessarily denote a filesystem in use (as  
you noted yourself), and
b) I am not 100% sure that "IDE64 will no doubt assume an xyz  
partition is IDEDOS FS" - I'd have to check that but I wouldn't be  
surprised if the superblock was checked at least for the FS signature

>   The other issue (not nearly as problematic, but still) is that  
> 0xcf is already a claimed partition type (0xcf is claimed by DR-DOS  
> Secure FAT FS).  As far as I can tell, 0xf8 is not used by anyone.

I tend to believe that DR-DOS (since unethically - yet effectively  
killed by Mircrosoft) clash is not what concerns most potential users  
of the iface in question. Still - see the first paragraph of my reply.

> As for the FS, I think it should be supported, but I don't know  
> that it should be the only one supported.  I think FAT should be  
> supported as well, for folks who want to mount their CF and then  
> pick it up and pop it into their PC.

As I wrote - reading FAT is supported in the current IDEDOS. For  
effective CBM use there might (?) be limitations preventing it usage  
without major workaround/encapsulating effort. How about Microsoft  
royalties. I heard (correct if wrong) that one has to pay licence  
fees for write support.

> However, beyond the use of IDE partition tables, I can;t find a doc  
> that explains the FS layout.  Without it, it will be very hard to  
> implement.

See previous post.

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