The main reason why you get no response to this question is because you ask
for assembler replies...
It has been the bane of Oricians lives, that the D/D is a difficult baby to
deal with in assembler.
Symoon has done work on using Assembler to directly call Sedoric commands,
as have I but to just quickly send you examples is not so easy.
Their are offcourse other ways to accomplish disc access, such as keep the
basic interpreter running whilst dumping the command you want into the input
buffer. This technique was often used on the C64 to load files on bootup
However, the problem is that you'll need to reserve all that *** space that
basic interpreter uses.
Another way is simply to return to basic and do the disc accesses in basic
code. I have usually done this when writing quick apps.
The other way is to use machine code specific to reading and writing to
sectors on the floppy. Fabrice, and Jede have accomplished this but it
requires a working knowledge of the low level architecture of the Oric D/D
and Disc itself.
When i get time (As if i get time thesedays!) i'll upload a link to
something more substantial than just words. ;)