[TUHS] Dennis's V6 root tape

Will Senn will.senn at gmail.com
Sun Nov 12 06:11:20 AEST 2017

Does anyone know if the image 
is somehow bootable as-is?

I wasn't able to figure out how to get it to boot, so I went on a quest 
to make it bootable. Here's what I did - let me know if this was 
overkill or misguided.

Basically, I downloaded the known bootable v6 distribution tape from 
Wellsch directory in TUHS. I then extracted 101 blocks from the image 
(tmrk, a bootblock, and who knows what else, but seriously what else is 
on those first 100 blocks?), converted it to a simh compatible tape 
format, and booted a simh generic pdp11/40 with my new little boot tape 
and Dennis's root disk attached. I used tmrk to copy the bootstrap from 
my little tape to Dennis's root disk (am I clobbering anything 
important?). Then voila - it was bootable :)! I could have done it 
straight off Ken's tape (after converting it to a simh tape format), but 
I wanted to keep the little tape image around for use in other contexts.

Details for the curious are here: 

I thought the Ken Wellsch tape was basically the same as the Dennis 
Ritchie disks, but now I'm not so sure - on Ken's tape, it boots to:

mem = 1035
Use, duplication or disclosure is subject to
restrictions stated in Contract with Western
Electric Company, Inc.

on Dennis' it boots to:

mem = 1036

Makes me curious to see what else is different. Maybe Dennis's was prior 
to preparing an official distro where the rights were added to the kernel?


GPG Fingerprint: 68F4 B3BD 1730 555A 4462  7D45 3EAA 5B6D A982 BAAF

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