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This directory contains the source code to the TSS/8.24 timesharing system
for the PDP-8.  This copy comes from a source listing that I borrowed from
the Melrose (Mass.) High School in 1984, typed in to my PDP-8/E (which came
from the Belmont High School but ran Melrose H.S.'s monitor), and proofread.
Then I cleverly dumped it to TSS/8 PUTR DECtapes for "safekeeping", and it
took me over a decade to get around to extracting the data (on a PDP-11),
and three more years to get around to finishing reverse-engineering PUTR.SAV's
DECtape format!  But here the files are, finally.

This should be an almost 100% vanilla DEC source set, unless some typos
crept in.  The only change I made was to fix comments that refer to the user
as "HIM" to say "HIM/HER".  What can I say, I was going through a P.C. phase.
Also, I inadvertantly had EDIT.SAV set in the mode where it expands any two
spaces to a tab on input from a file, so some things look funny, like the
DEC copyright notice.  The source for each 4 K component is broken into
pieces small enough to fit into the free space on my system's RF08/RS08
disk when I was typing it in, they should be concatenated before actual use.

This version is set up for an 8/E with 32 KW of core, one RF08/RS08 256 KW
disk unit, a PC8E/PC04 high speed paper tape reader/punch, an RK05, line
printer, card reader, and a bazillion KL8E terminals (I used an LC8E for K00,
which worked fine).  It seems to be a good sport about running with missing
hardware (my machine had no RK05, LP, or card reader, and ran this monitor
fine), except the RF08 of course.

There are lots of conditionals to tweak if you want to change the
configuration.  Normally this was done by DEC, they'd rebuild it using
the PAL-10 cross-assembler on a TOPS-10 system and ship the binaries (and
maybe a hardcopy listing) to the customer.  I'm not sure what needs to be
changed to make it build under PAL-8 on OS/8 but I've heard it's been done.
PAL-D (the TSS/8 assembler) doesn't support conditionals at all, so it
certainly couldn't be used...

CPU=4 seems to be a valid setting for the CPU model, although its meaning
is not documented.  Maybe it's for the PDP-8/A?

The sources to SI (the System Interpreter, i.e. command line interface) were
typed in separately a few years later, I ran out of steam typing in the
original listing so I photocopied the SI part so I could return the listing.
SI was typed into an IBM PC so it doesn't have the problem with two blanks
being translated into a tab.  Also, I split off the "parameters" and "linking"
sections into PARAM.PAL and LINK.PAL since it looks like they were constant
prefix files for assembling all five components, those parts should probably
be hacked off of the other sources so that one centralized file can adjust

Thank you very much to Bob McCann, who if I'm not mistaken was the person at
Melrose HS who loaned me the listing (in 1983 or 1984).  And thank you to
Ron Diamond (who went to M.H.S.) for brainstorming about M.H.S. faculty to
remind me of Bob's name (sorry, it was a long time ago!).

John Wilson <>, 18-May-2000.
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