MMU and serial ports are likely a lot simpler than the instruction
set. I am into Z180's so I'll probably try to do something there but
I am not so experienced.

I have just recently got some larger fpga's so will be doing some
more soon, a 16k zx81 fits very comfortably in a XCV1000E, 8K Ram
zx81 fits in a XCV800.

I can not fit things in as well as Daniel as I am only using xilinx
tools.

I think I will try some of the onchip stuff from the z180 but I am
not up to tackling the microcode yet.

In the meantime I am seeing how fast I can get a ZX81 to go in fast
mode (anyone got a use for a 200Mhz ZX81?)

cya, Andrew...

--- In zxgate@yahoogroups.com, "James Diffendaffer"
<jdiffendaffer@y...> wrote:
> Have you worked on any of this? I'm mostly interested in the TRS80
> since it's what I learned to program on. I am also interested in
> adding 64180 compatibility to the processor core... however I'd
> probably just start with instructions rather than the MMU, serial
> ports, etc.
>
> --- In zxgate@yahoogroups.com, "Daniel Wallner" <jesus@s...> wrote:
>
> > I will make sure that the
> > Spectrum's RGB and S-Video outputs work and possibly fix the ZX81
> > and TRS80 problems but that's it.
> > Only the ACE is at the moment complete and there are lots of
things
> > to do, especially on the TRS80 and the Spectrum.
> > Is anyone interested in doing this?