Re: Not your father's Applicard

[alex.freed.007@gmail.com]

On Jan 7, 6:12 pm, Steven Hirsch <snhir...@gmail.com> wrote:
>
> Cool!  I want one!  Is that larger DIP package to the left of the EPROM a
> static RAM?

Yes. A 128K static RAM with 55 nS access time is very affordable. And
there are same spec 512K chips in the same case. So up to 1 MB can
be mounted.


>
> Feel like tackling the CardZ180 next?  I think the HD64180/Z180 chips are
> still available, and at smoking clock rates :-)  (Some people are just never
> happy..)
>

It won't be any harder. In fact no need to do memory management - z180
takes care of it. The only thing is I need an operational board with
the
software for it and at least some parts of the BIOS source.

I'd love to have one myself - the UART will be quite useful.


> Nice work.

Thanks, but I was to quick to post. Not fully operational yet. It is
100%
consistent. Loads the first few blocks, copies OS to the z80 space,
wants to load some file (likely DRIVERS) but fails with banging the
head against the wall - recalibrating the drive. Prints the message
and doesn't respond any more.

It LOOKS like a bad disk sector, but I made 3 floppies with the same
result. I need to trace what the 6502 disk driver does, I guess.

Once it operates 100% I'll take pre-orders and see if we reach a
critical mass for professional assembly. If not, I may just offer
kits with a board and programmed CPLD and PROM.



-Alex.