In reply to: Bret Johnson <bretjohn@ju...>
>> only support Intel/Via (UHCI) controllers yet.
> True. Working on that.
>> I also think they have hard coded 512 bytes per sector.
> No. USBDRIVE reads the maximum buffer size from the DOS List of Lists (as
> discussed some earlier in the thread), and uses that as its maximum sector
> size. If a USB disk has 4k sectors, but DOS can only handle 512 byte
> sectors, USBDRIVE won't load the disk. If DOS can handle (buffer) 4k sectors
> OK, USBDRIVE will load it and automatically mount any FAT partitions it finds.
TY for the heads-up.
> Also as stated earlier, I don't personally have any disks with sector sizes
> other than 512, so this has never been tested (at least by me) on a real
It would be a good thing if someone on the list having access to such a device
/and/ Intel-based USB would experiment and report their findings...
> That's why you need to modify the kernel to handle 4k sectors, also as
> discussed earlier (at least with my drivers). Based on what Eric says,
> though, that doesn't work with the FreeDOS kernel.
As I noted earlier, I'm sure the default disk driver MS DOS kernels can handle
bigger sectors, /but/ there are problems to be fixed - as pointed to me by R.
Loew, and I verified it too : MSDOS init module (patition scanner) discards
partitions whose boot sectors indicate any sector size other than 512. Disks
operated through user drivers (config.sys) should not be so limited.
While trying a free fix for MSDOS could be attempted - but is the effort worth
it ? - I would vote for FreeDOS to be enhanced.
Does someone here know if DR/Open DOS recognises >512k sectors, either or both
with its built-in disk driver and user drivers ?
> Because USBDRIVE provides an INT 13h interface, you can also use external
> drivers to mount/access the non-FAT partitions that may be on the USB disks
> (NTFS, EXTx, exFAT, ...). USBDRIVE won't mount non-FAT drives automatically,
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