UNIBUS M9312 ROMS

Don North ak6dn at mindspring.com
Wed Jun 8 20:02:18 CDT 2016


On 6/8/2016 5:56 PM, Mike Ross wrote:
> On Thu, Jun 9, 2016 at 12:27 PM, John Robertson <jrr at flippers.com> wrote:
>
>> No way the M9312 can self modify, it is a burn once PROM -
> I kinda assumed it was a case of copying itself to RAM and
> self-modifying as it runs there - if it ever happened.
>
> Mike

As it happens the 23-760A9 TT/PR boot PROM does this copy by building a bootstrap
sequence in RAM, and then jumping to it. Once it is built it is not self 
modifying, however.

Ref:  http://ak6dn.dyndns.org/PDP-11/M9312/23-760A9/23-760A9.lst

-- 
Don North
AK6DN



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