Re: Not your father's Applicard

[alex.freed.007@gmail.com]

On Jan 8, 6:52 pm, David Wilson <mcs6...@gmail.com> wrote:
>
> This would probably make graphical programs slower (as the data has to
> be fed though the 1 byte register rather than written directly to
> video RAM) but CPU intensive code would be faster (no need to give up
> cycles to keep the 6502 refreshed and z80 can run at higher bus speed
> than the host).

Sure no shared memory makes graphics slower, but I'm not sure how many
CP/M graphics oriented applications are there. AFAIK there was no
standard
for graphics in the CP/M worls before the MSX (not well known outside
of
Japan). On the other hand you can write a 6502 program that renders
graphical objects from some sort of "vectors" sent from the z80 side.
Just
like the terminal programs get a byte or two as a command and do
things
like "scroll the screen".  With 2 CPUs running at the same time, could
be
quite efficient.

In fact quite a few interesting things can be done with this card even
without
CP/M loaded. For example the PROM is 32K and less than 2 K is used.
Store programs making some very fast calculations there and use the
card
as a co-processor for 6502 programs. Even store short fragments of
code
or data that can be quickly copied into the 6502 memory space.

>
> I think I would be interested in one of these - even more interested
> if it had a z180. I would be happy with a kit version - PCB + CPLD +
> any hard to get parts. I have many machine pin DIP sockets and may
> even have a suitable RAM chip - I would have to check.

I have stated the pre-requisites for making a z180 version happen.
Doesn't look very likely to happen soon.

Now I need to find a way to do an accurate count. Maybe just e-mails
that I will consider "binding contracts".
The idea is very simple. Each e-mail will state for example that you
would buy a finished card as a first preference at $100 or a kit with
the board and all the parts for $50. Partial kits don't make a lot of
sense IMHO, but use your own CPU if you want and pay $45 as
I plan populating 10 MHz CPUs that are $4.92 each.

I'll wait say a week and count all the messages. If I get 20 full
board
requests, I'll do a "production run". If not, I'll just order PCBs and
parts for the kits. If less than 10 kits are requested they may cost
a few bucks more per board.


-Alex.