In the CSRG DVD set there is some cci ports of 4.2BSD… stuff is #ifdef’d Tahoe in there so it’s not hard to pick out but it doesn’t seem to have anything really documents looking.

I could be 100% wrong though, but they just look like ‘clean’ source trees. Not sure if sanitized though.

The assembler shows 182 opcodes …

/*

* Boot program... arguments passed in r10 and r11 determine

* whether boot stops to ask for system name and which device

* boot comes from.

*/

/*      r11 = 0 -> automatic boot, load file '/vmunix' */

/*      r11 = 1 -> ask user for file to load */

The stand/boot sounds awefully vax like with r10/r11…

From: Clem Cole
Sent: Wednesday, 26 May 2021 11:22 pm
To: Lars Brinkhoff
Cc: Jason Stevens; tuhs@minnie.tuhs.org
Subject: Re: [TUHS] H.J. Lu Bootable Root & Base System disks

Really good point -- I saw some years ago, but never owned a copy.

ᐧ

On Wed, May 26, 2021 at 3:57 AM Lars Brinkhoff <lars@nocrew.org> wrote:

Jason Stevens wrote:
> It took me years of on and off to finally figure out what the heck a
> Tahoe even was.  Spoiler for anyone who wasn’t there when it happened
> it’s a Harris HCX-9.
>
> But then again there is some movement on an RT emulator and there is
> the 3b2 stuff so maybe there only needs to be a ‘push’…

Is there even a single shread of documentation though?  It's a daunting
task trying to write an emulator based only on inferring the internal
workings of the machine from 4.3BSD source code.  Mind, the end result
wouldn't be too interesting; hey it works... just like a VAX.