12 Dec
2003
12 Dec
'03
11:13 p.m.
On Sat Nov 29, Tom Jennings wrote:
I just added a bunch of LGP-30 software to my website
(http://wps.com/LGP-21) including the Subroutine Manual I got
from Bob Lilley, as well as the Notes from a college programming
course he taught in the early 1960's.
The Subroutine Manual for the '30 is a goldmine, as it contains
the bootstrap and all the input routines.
The site is indeed very interesting. In our computer museum at the
University of Stuttgart we have a complete working LGP-30 with Flexowriter
and high-speed reader/punch since 1999; it is probably the only working
machine on earth. I met David Weil of the Computer Museum of America last
year and I gave him a copy of the german maintenance manual including
schematics of the LGP-30 and all our paper tapes (read in on a PDP8/e and
transferred to a PC with Kermit) on a floppy disk. In return I copied the
essential parts of the american LGP-21 maintenance manual (not the
complete manual because of the excessive high costs of $0.10 per side) and
extracted the wiring diagram of the little daughter board which is in my
eyes an instruction set modification. There were many such
modifications/enhancements for the LGP-21 for which we have all the
documentation and blueprints and I know of a modification for the LGP-30
which added a -Z instruction and an overflow flag in the program counter.
I have reengineered this and added it to one of our two LGP-30 logic
boards. It is working but we have no software which makes use of this new
feature.
We have the original and complete sets of schematic diagrams,
blueprints and software for the LGP-30 and LGP-21 (except SW). For those
who are interested the LGP-30 papertapes can be found at
ftp://ftp.informatik.uni-stuttgart.de/pub/cm/lgp30/papertapes
and some pictures and (german) description (needs to be updated) at
http://computermuseum.informatik.uni-stuttgart.de
The paper tapes include the Act V compiler, basic subroutines, 10.4
(successor of 10.0) and 9.0 (bootstrap loader), as well as the original
Blackjack game (yes, it's there!) and other stuff. All tapes have been
converted to ASCII but there are tools to convert from ASCII to FlexCode
and vice versa. I have also written a LGP-30 simulator for
MS-DOS (written in Turbo Pascal) that runs all LGP-30 software. I have not
published it yet because I have to cleanup the code and translate the
messages into English. I will put it onto the ftp server if this is done.
I would be very happy for any comments and discussions on the LGP-30 or
LGP-21, especially if there is another *working* LGP-30 out there. Our one
was built in 1958 and it's working perfectly, the drum has no "bad
sector"!
Christian
PS: Here's a transscript of my simulator running Blackjack. The output is
in color (black and red) and it appears to be the same program as the one
on Tom's site.
*** LGP-30 Simulator *** HALT
(C) 2000-01 Christian Corti
5 - c 7 - s
4 - s
Card? yes 9 - s
Card? Q - h
total - l8 total - l7 score = $l.00
J - h Q - d
K - h
Card? 2 - s
J - c
total - 20 bust score = $2.00
l0 - h 4 - d
7 - c
Card? Q - s
9 - d
total - l7 bust score = $3.00
[...]
7 - d l0 - s
J - d
Card? 9 - s
total - l7 total - l9 score = $l.00
8 - d 3 - c
3 - h
Card? yes A - c
Card? yes A - d
Card? yes A - h
Card? yes 4 - s
Card? 2 - s
2 - h
A - s
5 cards total - l8 score = $3.00
[...]