> Dear List... I'm calling back with respect to the 4k-sector USB disk  
> drive. I'm considering writing a loadable DOS 'block' driver for it, as  
> Eric Auer suggested.

This doesn't belong on Freedos-user then.

> I would like to take the simplest approach possible first, even at the  
> expense of performance. My driver would be little more than a 'shell'  
> around USBASPI.SYS.

What exactly do you want to accomplish with that?

> - Using a loadable driver for the block device implies DOS won't use  
> /its/ internal buffers, so I don't have to care about DOS own buffers  
> sizing, right ?

This is wrong. Block drivers directly interact with DOS and its buffering  
scheme. If what you want is to circumvent the restrictions imposed by  
DOS's buffering scheme (for example, current 512B-/2048B-sector limits of  
the FDK) you'll have to write your own (FAT) file system driver which  
interfaces downwards with the block device driver (in your case,  
USBASPI.SYS) and upwards with DOS's file system redirector interface. (The  
redirector interface is what file system drivers for non-FAT file systems  
(eg *CDEX) and networked file systems use to make their files accessible  
to DOS. Your case, as I understand it, would be a special case to  
circumvent DOS's FS driver's limits.)

C. Masloch

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