PDP11 Plessey disk drive info needed

From: Jgzabol_at_aol.com <(Jgzabol_at_aol.com)>
Date: Thu May 6 01:54:02 1999

In einer eMail vom 05.05.99 21:02:46, schreibt Tony:

<<
> That is EXACTLY what I need - the connector has the letters above
imprinted,
> and the meaning of the signals I have from the DEC docs. This is precisely
the
> RK-11 Drive Bus.
 
 It's _almost_ the RK11 bus. Not suprising since the Diablo/DRI model 30
 was sold by DEC as the RK02/RK03 for a time. I've cabled one up to an
 RK11-C, and it is, indeed, just a cable.
 
 The problem is in the drive select lines. RK11-C's use 1-of-4 code (you
 assert one of 4 lines, like on a floppy drive). RK11-D's use a 3 bit
 binary selection code. RK05s can handle either (there's a signal on the
 connector of an RK05 that is pulled low by an RK11-D to indicate this).
 RK02's, etc can't.
 
 That's why you'll need a couple of chips to do the interfacing.
 
 -tony
 
>>

Hi Tony,

I am aware of that fact. It is of course a very simple decoder. Since I will
need to mate two different cables (one from the drive with the 42-pin
connector, and another one from the controller with the bus paddle) I will
have a little intermediate board anyway, where this can easily be put.

First of all, of course, I will need to verify that the Plessey interface is
in fact identical to the Diablo one; since the connector is the same, I am in
good hope.

Regards
John
Received on Thu May 06 1999 - 01:54:02 BST