Re: AE PC Transporter

[dempson@actrix.gen.nz (David Empson)]

Frank Carney <frankcNOSPAM@cyberhighway.net> wrote:

> Actually I found the information I was looking for.  Both the V30 and
> V20 CPUs are capable of i8080 emulation.  The Z80 processor, although
> not pin compatible with the i8080, is instruction compatible with the
> i8080.  So it is possible to run CP/M on that processor.  However, you
> would probably have to rewrite parts of CP/M so it will boot properly.

The Z80 instruction set is a superset of the 8080 instruction set.  This
means that the Z80 can run code written for the 8080, but the opposite
is not necessarily true.

CP/M itself (version 2.2, at least) is written in 8080 assembly language
(the BDOS, command processor and standard utilities), so these parts
should work unchanged.

The BIOS is system specific, and one would have to be written for the PC
Transporter.

The major catch is that many of the useful CP/M applications make use of
Z80 instructions, and these programs will NOT work on an 8080 (or a V30
in 8080 emulation mode).

Some applications might be even more system-specific, e.g. relying on
hardware features of a particular Z80 card or the host machine.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand