Subject: TC01 bootstrap requested
From: Charles Lasner <[email-masked]>
To: [email-masked]
Date: Wed, 5 Jun 91 17:31:46 EDT

Date: Wed, 5 Jun 91 17:31:46 EDT
From: Charles Lasner <[email-masked]>
To: [email-masked]
Subject: TC01 bootstrap requested

    This was all worked out years ago, but in response to a recent
request:

From: Charles Lasner <[email-masked]>
To: Klaus Zeuge <[email-masked]>
Subject: Re: Bootstrap for 8/I from TU55/TC01
In-Reply-To: Your message of Wed, 5 Jun 91 22:59:26 +0200

    OK, a TC01/08 bootstrap for you!

    Here are a few:

    ALL require the following:

    7754/ 0000 through 7577; 7577 is less switch manipulation due to next
    7755/ 7577

    Some people like this one, especially if you have to rewind the tape
because you don't know where the end zone is.

    0600/ 7604
    0601/ 6766
    0602/ 5202

    First wind the tape on 'til it's clearly way past the end zone; this
necessitates a rewind.

    Set the switches to 0600 and do the load address and start.  The
0600 in the switches makes the tape rewind.  It will stop automatically
on the tape error which should be an END error.  All else is wrong, and
means stop the machine and load address and start again.

    Once the tape is clearly in the end zone (because of the END error),
then you can actually boot the machine.

    Load address 0600 then change the switches to 0220 THEN start.  The
tape should move forward slightly.  Probably stops with a timing error.
As a validity test, note that 7754 is now 0000 and 7755 is now 7777.  If
not, it didn't work :-(.  If it did, then just start at 7600.

    The whole thing can be moved to 7615-7617 if you want.  This saves
the manual startup step because it overlays the toggle-in code directly:

    7615/ 7604
    7616/ 6766
    7617/ 5217

    Load address 7615 and then change switches to 0600 and start.  Same
stop as above version.  Then load address 7615 again, changing switches
to 0220 and start.  It will just come up if it works, but no chance to
find out what was wrong if it doesn't.

    Additionally, if you have "intimate" knowledge of the tape format,
you can wind the tape on to the end zone and just do the 0220 part.  It
doesn't matter where within the 6 feet of formatted end zone area it is
:-)

    As long as you format your own tapes consistently, you can figure
this out.  The PROPER way to format tapes is to make the tape just
barely hang on the reel; let the program wind the tape.  Some people
make the mistake of thinking the tape format needs some form of blank
"leader" so they wind it on up to thirty feet :-).  The formatting
program creates the appropriate leader, end zone, etc., itself, so
clearly you should just hang it on, not any further when running the
formatter.  This also means that for boot purposes, you can just put the
tape up, and merely wind it a few inches, and it is suitable for the
above boot procedure bypassing the end zone rewind step.

cjl

From: "Rev Phil Herring, DD (Ret." <[email-masked]>
Mmdf-Warning:  Parse error in original version of preceding line at mc.lcs.mit.edu
Subject: A PDP8 simulator via FTP
To: [email-masked]
Date: Fri, 7 Jun 91 14:04:07 EST

From: "Rev Phil Herring, DD (Ret." <[email-masked]>
Mmdf-Warning:  Parse error in original version of preceding line at mc.lcs.mit.edu
Subject: A PDP8 simulator via FTP
To: [email-masked]
Date: Fri, 7 Jun 91 14:04:07 EST

In article <[email-masked]> [email-masked]
 (Kevin Fitzpatrick) writes:
>I teach an architecture lab using a PDP-8 simulator that runs on a PC.
>The textbook (which contains plenty of PDP-8 code) is...
>
>    N.A.B Gray, "Introduction to Computer Systems," Prentice-Hall,
>       Australia, 1987.
>
>    US ISBN 0-13-480386-8

The source for this beast (a curses-based, fairly complete PDP8 simulator)
can be ftp'd from 

	wraith.cs.uow.edu.au

The file is pub/pdp8.tar.Z

(No documentation I'm afraid - but I'm sure Neil won't mind you buying 
the textbook :-)

-- Phil.
-- 
        These opinions (c) 1991 Phil Herring ([email-masked])

"I *will* point a gun for my country, 
but I can't guarantee you which way"  - Woody Guthrie