Hi guys,
A few of you might be aware of my AT&T 3B1 (UNIX PC) emulator project,
FreeBee:
http://www.philpem.me.uk/code/3b1emu/
A few of you may recall my... less than flattering comments about the
hardware manual. Long story short, the PAL equations in said manual are
worthless. Too many logic terms are missing or incorrect.
To that end, I'm looking for one of the following:
A complete 3B1 system. Hard drive optional, I have a couple of ST506
hard disk drives here which could be pressed into service if need be.
This would probably be cost-prohibitive unless the machine were already
somewhere in the UK or EU (probably one of the units Olivetti imported,
rebadged and sold).
A motherboard and keyboard (and ideally the internal cabling). I'm
reasonably convinced I could put together a power supply and some form
of display, but the keyboard would be a pain to substitute.
A set of PALs (labelled with their board position) and gate arrays (or
the bodgeboards used in early-rev 3B1s) which I could read out and
decode to produce a full set of logic equations. My main target is the
Memory Mapper PAL.
I'm not afraid of taking a "breaker" unit and fixing it up. Broken is
fine, as long as it's something fixable (e.g. it dies during the poweron
RAM test without ever displaying the AT&T startup banner).
My plan is to dump the PALs and other programmable logic chips, then
hook up a logic analyser and document the behaviour of the gate arrays
(one of which is completely undocumented).
If anyone has any leads on any of the above kit, please either reply
here or contact me off list if you prefer.
Of course, if you'd like to contribute code to FreeBee, I accept Unified
Diff files by email, Dropbox or FTP :)
Andrew Warkentin has done a terrific job of making it work >95% - it's
just that last 5%.
At the moment it boots the Foundation set install media to userspace but
fails to mount the hard disc on /mnt, instead spitting out a "no space"
error followed by several "no stack space" errors). The prior
mkfs/install loader operations work fine...
Thanks,
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/