[TUHS] Bootstrapping UNIX - how was it done

[Paul Winalski via TUHS]

On Mon, Mar 23, 2026 at 12:20 PM John Levine via TUHS <tuhs at tuhs.org> wrote:

> It appears that Peter Weinberger (温�  � �) via TUHS <pjw at google.com> said:
> >As I remember, the 11/70 was booted just as John describes. One keyed
> >in a boot loader at the console.
>
> I'm pretty sure our PDP-11 at Yale had a boot ROM, so you just set
> the starting address from the switches and started it.
>
> Before that I toggled boot loaders into PDP-8's and I don't miss it.
>
> The 11/70 most certainly had a boot ROM--the M9312.  Perhaps the version
of Unix in question wasn't compatible with the M9312 bootstrap loader, or
they just preferred their own bootstrap loader to the M9312?  Or maybe they
didn't have a M9312 installed.

-Paul W.