shirsch
Veteran Member
I read the ST-412 (RD51) drive into a sector image using Dave Gesswein's mfmemu and would like to loop mount the MSDOS partition under Linux and read out the files. So far I've been able to decipher the Rainbow partitioning scheme (described in the DEC MS-DOS manual), determined that a +7 skew was used and wrote a quicky utility to de-interleave the data. I can see a valid FAT table and root directory. Problem is that Linux FAT support and the various utilities I've tried want to see a conventional MBR and partition boot sector. DEC went their own way and there is nothing resembling the usual 512 byte blocks ending with 55AA. So unless I'm missing something obvious it looks like I need to synthesize these bits and prepend them to the start of the FAT.
After a bit of study I'm almost ready to put the pieces together. The point I'm stuck on is that I need to know these bits of information about the filesystem:
After a bit of study I'm almost ready to put the pieces together. The point I'm stuck on is that I need to know these bits of information about the filesystem:
- Sectors / Cluster
- # of FAT copies
- Max # of root directory entries
- Sectors / FAT copy