256-byte sectors

[mark_k]

I've been experimenting with how well (or not) 256 bytes/sector drive and partitions are handled. [Some FFS versions up to at least v36.104 support partitions with 256-byte blocks. Which of course need to live on a 256 bytes/sector drive.]

Creating a partition HDF and mounting using a mount file on the Amiga side works OK. The mount file gives the exact filesystem. ROM FFS might be v40.1, but there's a line like FileSystem = L:FFS_36.104 in the mount file. Some later FFS version removed support for 256-byte blocks, but I'm not sure which.

Creating a partition HDF and having WinUAE mount it at boot time (specifying FFS 36.104 in hardfile settings window) also works. Bootable too.

With an RDB hardfile, I could partition it and install FFS 36.104 to the RDB area using HDToolBox, though I don't think HDToolBox really supports 256-byte drives properly; there's no 256 option in the filesystem block size cycle gadget. But it seemed to work, and booting from the 256 byte/sector partition works. Doing Version UDH0: reports "filesystem 40.1", so it's using the ROM FFS instead of the earlier version in RDB. Does FFS 40.1 support 256-byte sectors? It seems to.

Do all SCSI controllers use the ROM filesystem if it's a later version than the one in RDB?


By the way, I noticed something in the Scout system monitor's Mounted Devices window. In the Handler or Device column, partitions mounted at boot (by UAE boot ROM) show as "uaehf.device". If you double-click the partition entry in the list, the info window shows Handler: <none> and Device: uaehf.device. Whereas for a partition mounted after boot, Scout shows (for example) Handler: L:FastFileSystem_45.13.

Is that difference normal, or do other SCSI controller boot ROMs allow Scout to show the current handler for mounted-at-boot-time partitions? (I was trying to check which FFS version is in use for my 256-byte partition.)

[Toni Wilen]

Do all SCSI controllers use the ROM filesystem if it's a later version than the one in RDB?

Thats how they are supposed to work but who knows..

By the way, I noticed something in the Scout system monitor's Mounted Devices window. In the Handler or Device column, partitions mounted at boot (by UAE boot ROM) show as "uaehf.device". If you double-click the partition entry in the list, the info window shows Handler: <none> and Device: uaehf.device. Whereas for a partition mounted after boot, Scout shows (for example) Handler: L:FastFileSystem_45.13.

Is that difference normal, or do other SCSI controller boot ROMs allow Scout to show the current handler for mounted-at-boot-time partitions? (I was trying to check which FFS version is in use for my 256-byte partition.)

It is normal (and correct behavior). Handler (pointer to filename) is only set if file based handler is going to be loaded. RDB loaded filesystem is not a file and is directly pointed to by SegList pointer.

EDIT: Use UAE debugger to see which filesystem is in use. TO shows all dos devices, check its SegList, then use Tf to list FileSystem.resource contents. Match SegList to FileSystem.resource entry. (and remember BPTR conversion)