This site is dedicated to the investigation of computer hardware and software that preceded the so-called "IBM PC".  Many types of old Z80 based microcomputers are in my collection.  I enjoy trying to keep them running and disassembling their firmware and operating systems, and the application programs that ran on them.
I've been trying to rebuild my old web site, so this is only a partial snapshot of what used to be there.  If you want to view the full  content of the old web site, you can go to:  www.oldcpusrus.xepb.org .  Local domain name services might not translate that domain name.  If that is the case, just add it to your known hosts (in /etc/hosts) like this:        www.oldcpusrus.xepb.org

-classic 8-bit microprocessors
-system pictures

This site is currently under construction.

E-mail contact:


"Unofficial" CP/M
Gaby Chaudry's great site
"Commercial" CP/M
Gene Buckle's commercial
CP/M software site
Herb Johnson's Retrotechnology
"Retro" computer parts, documentation, and info.
CP/M Rights
Caldera transferred the rights to
CP/M to Lineo, Lineo sold them to
S-100 Resource
S-100 part of Herb Johnson's site
(parts, manuals, and info.)
Obsolete Computers
Tom Carlson's Obsolete
Computer Museum
Obsolete Computers
Tom Copper's Collection
Vintage Computer Info.
searchable hardware and
software archives
Dick Perron's site
good info. on "newer" old hardware
(mostly PC's, some others)
Z80 Projects
Thomas Scherrer's Z80 page
John Elliott's Site
info. on CP/M
(good source in the UK)
John Pierce's Site
burrow down and you'll find some
photos and info about Digital Research
Chip Directory
chip info. and I.D.
datasheet archive
Hal Bower's Site
CBIOS and Banked Bios info.
University of Virginia
computer museum
Hans Summers' Site
lots of good Z80 information
and projects
Classic Computers
Classic computing
More Old Computers
Photos of, and descriptive info.
for, many of the classics
The Cro'sNest (lives!)
Cromemco S-100 Computers
Gold mine of old software,
firmware and documentation.
Grant Searle's Site
brilliant design of 9-chip CP/M computer
Alan Paton's Interak Site
uDrive and C.F. info.
P112 kits and support
more good P112 info.
Source Forge
The Source Forge P112
MicroCode Consulting
Legacy Z80 and KayPro
Bill Buckels' Site
CP/M 80 and 86
Dave Dunfield's Site
software and hardware,
Marcus Bennett's Site
great archive of S100
information (h/w and s/w)
Google Cromemco Group
discussions and postings
Manuals for old hardware
from Howard Harte
John Baker's Projects
good reference, esp. 8-bit IDE
John Monahan's S-100 Archive
pics./docs./info for S-100 hardware
A Programmer's Notebook
Utilities for CP/M-80
by Dave Cortesi
Dr. Dobb's Z80 Toolbook
by Dave Cortesi
by Werner Cirsovius
CP/M Development
CP/M software and info.
by Douglas Goodall
Znode 51
Web incarnation of the old Z-node 51
by Helmut Jungkunz
Z80 RetroComputing
8BitGeek's Retro Computing
CP/M Languages
Peter Schorn's collection of
languages for Altair CP/M 2.2
Udo Munk's Z80 CPU Simulator
Z80pack repository