Re: Returning Apple User

[Alex Freed <alex_news@mirrow.com>]

Steven Hirsch wrote:
> The CardZ180 uses an Hitachi HD64180 / Zilog Z180 CPU and makes use of 
> that processor's ability to bank select from large physical memory 
> spaces.  At a minimum, you might be able to get away with simply 
> emulating the additional functionality on top of a Z80 core (a handful 
> of additional opcode, IIRC). I'd have to check the software and see if 
> it will run without banked memory.
>
> Otherwise, probably best to stick with something like an Applicard 
> clone. That's a vanilla Z80 design with its own 64k bank of memory.  I 
> do have the schematics for it and it's all 74-series jellybean logic.
>
> Let me know if you need this?


The schematics would be very useful, thanks. I searched the net but
could not find any info on the software model of the Applicard except
general words that it shared no memory with the 6502 and only used
"a few registers" to communicate.

A have several soft Apple2 clones inside FPGAs. Including one with a
(soft) z80 that emulates the MS SoftCard. It works fine but only at
effective 2 MHz. It would be almost trivial to modify the glue logic
in my Verilog to emulate a much faster Applicard. I have lots of RAM
on the board for the additional bank. I only need the schematics and/or
register level description of the circuit and the boot EPROM.

> Steve

-Alex.