The BAM and directory sectors are set in the format command. After formatting a disk, I have moved the directory sectors to different locations. You just have to be sure to change the link information in the previous sector in the chain. You can read or write files with this changed structure. I do not know what happens if you need more directory sectors than you have allocated. On Thu, 30 Nov 2017, MichaÅ~B Pleban wrote: > Hello > > Is it possible to move the BAM to a different place on the disk (I am > speaking specifically about 8050 and 8250 drives)? Looking at the disk > structure, it has first directory sector at 39,0, which then points to > 38,0 (first sector of BAM), chained through 38,3, 38,6, 38,9 up to 38,1 > (second directory sector). So the question is, does the drive actually > follow this chain (which would mean the BAM sectors could be placed > anywhere) or is their location hardcoded in the drive DOS and this chain > is just a leftover? > > The rationale: my PC IMG to D80/D82 conversion tool reserves tracks 38 > and 39 which contain the BAM and directory. The idea is that the user > can do DIRECTORY from Commodore BASIC and, more importantly, the PC > emulation layer files can be placed there. > > But there are only 25 free sectors on track 38 in 8250 image, and the > software already uses 22 of them, leaving only 3 sectors free for the > software to grow. But if I moved the BAM to track 39 [*], I could gain > additional 4 sectors. > > Regards, > Michau > > [*] Yes, I am aware that if you were to place hundreds of files on the > disk, the growing directory could overwrite these BAM sectors. > > Message was sent through the cbm-hackers mailing list > wlevak@sdf.lonestar.org SDF Public Access UNIX System - http://sdf.lonestar.org Message was sent through the cbm-hackers mailing listReceived on 2017-12-01 06:00:02
Archive generated by hypermail 2.2.0.