On Thu, 2006-03-09 at 14:20, bill perkins wrote:
> >
> >
> Yup, I ran HDOS- it wasn't bad, and the source was available; I bought
> the books when they were discontinuing them. HDOS was written for the
> 8080, though, not a Z80 instruction in sight! I added a patch to map
> some reserved space to RAM, wound up with 56K RAM and 8K ROM thereby,
> and another patch to allow the modem to tie in directly to the terminal,
> so I could access the system from work. I got to show my boss what an
> actual assembler could do, as opposed to typing hex codes into an EPROM
> burner. My boss went to up to the Pres's office and snagged the only PC
> in the building, bought a cross assembler for Z80, and the rest (for me)
> was history.
Speaking of Z80 machines, does anyone remember the MAX80 and LDOS?
I did most of the port to that box and it had a chunk of 'slow'
ram somewhere above the keyboard memory map area. The engineer
that designed it already had CPM working and I used similar
code for the disk driver - and it took most of a day to realize
that the reason it didn't work was that under LDOS it had happened
to land in that slow ram area and just wasn't keeping up with
the controller.
--
Les Mikesell
lesmikesell@xxxxxxxxx
