On 2014-02-13, Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:
> An S-100 wire-wrap board.
Yup, been there done that!
I had a second-hand, off-the-shelf S-100 Z80 CPU board, a second-hand
S-100 memory board with 4KB of DRAM (eight 4Kx1 chips) and 2KB of ROM
(eight 256x8 Intel 1702A EPROMS), a home made backplace PCB with 5 or
6 slots, a home-made S-100 wire-wrapped board with two UARTs and some
other miscellaneous stuff. I shoved it all into rack-mount Motorola
Exorciser chassis I pulled out of a dumpster.
> I hand assembled a monitor program with, as I recall, 0..F, High,
> Low, Store, Go functions for the keyboard/display.
I was living large: I had access to an Intel MDS-800 "blue box" system
in one of the University's labs. It ran CPM with dual 8" floppies and
an EPROM programmer. [I think it also may have run some proprietary
Intel OS, but I was a CP/M man.] I typed in an assembly language
monitor program out of some book or other, assembled it on the
MDS-800, burned the ROMs, hooked up a borrowed Lear-Siegler ADM3A
terminal to my wire-wrapped serial board, and it actually worked for a
little while before something failed. Building reliable wire-wrap
stuff is a real art -- unfortunately one I never learned. It also
could have been the backplane that failed: the S-100 bus connecters
never _quite_ lined up preciesly with the card cage's guides, so there
were probably mechanical stress issues.