23 Sep
2022
23 Sep
'22
5:22 p.m.
On Sep 23, 2022, at 1:09 PM, Joshua Rice via cctalk
<cctalk(a)classiccmp.org> wrote:
...
The Cray was often coupled witha DG nova for bootstrapping, which very much did have a
front panel on it. Indeed, many models of PDP-10 were bootstrapped by PDP-11’s with front
panels, even if the PDP-10 lacked one. The CDC Cyber however, had “dead start” panels
hidden behind shouding, which could be used in a very similar way to a front panel.
I view the deadstart panel as a type of boot ROM, different from other boot ROMs only in
that it's easy to change. It was tied to an I/O channel; the deadstart operation
would run an I/O read operation on that channel to load the initial bits of code.
It's definitely not a front panel in the usual sense of a set of controls that are
used to interact with the machine while it is running. It only comes into play when you
hit the deadstart button to reset the whole machine back to its initial state.
paul