Need Info on DEC 11/84 Board, M8190

From: Megan <mbg_at_world.std.com>
Date: Sat Oct 17 21:36:49 1998

>To further complicate matters, within digital the CPU is identified
>differently based on whether it has PMI memory installed or not.
>(And, of course, it matters whether the PMI comes before or after
>the CPU in the backplane!) So, for example, you may find a 18 MHz
>CPU with non-PMI memory called a 11/73, but with PMI memory it's called
>a 11/83.

In fact... you could find the system with PMI memory, but installed
in the wrong place, and it will be identifed - by software - as an
11/73B. If you put the same memory in the right place, it will be
identified as an 11/83.

>If, indeed, you have the 11/84 capable version, you'll also need the
>KDJ11-B and the 11/84 backplane, along with PMI memory, to have a
>real 11/84 CPU.

But the board with Qbus memory in the qbus of an 11/84 system box
should work...

I've also taken one of the KDJ11-B 18mhz boards, removed the 18mhz
clock and replaced it with a 20mhz clock... the boot ROM correctly
identifies the clock speed, and the system runs rock solid...

be warned - not all boards will do so, from what I understand...
your milage may vary... etc... If you make the change and it doesn't
work, don't blame me... (save the old clock).

                                        Megan Gentry
                                        Former RT-11 Developer

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Received on Sat Oct 17 1998 - 21:36:49 BST

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