RX50 / RX33 Questions related to PDP-11's

From: Pete Turnbull <pete_at_dunnington.u-net.com>
Date: Thu Oct 15 15:46:16 1998

On Oct 14, 18:28, Zane H. Healy wrote:
> Subject: RE: RX50 / RX33 Questions related to PDP-11's
> >What exactly do your "RX33's" do when you try to access them?
>
> They flicker briefly just prior to the machine complaining it can't boot.
> I'm not sure I had them connected properly. I'll try the method Allison
> suggested in a little bit.

That sounds suspiciously like what the controller does to "sniff" an RX50.
 There's a bit of majic between the side select and track zero signals on
an RX50, which the controller uses to test that it's a real RX50.

> Well, the stickers are pretty hard to read, but if I'm looking at the
right
> two, they both say
>
> LMB617 or LM8617
> then one says 21725 or 217E5
> I'm pretty sure the second says 216E5

That's 23-216E5 and 23-217E5, the first version of the RQDX3 code. The
second revision is 23-244E5 and 23-245E5, which I think does support RX33s.
 The 23- means a ROM and the E5 means 16Kbytes (ie a 27128 EPROM).

> If these aren't ROMs that support RX33's which ones should I be looking
> for, there is a chance one of my other RQDX3's that I've got in my spares
> will work.

There was a third version, which was a minor bugfix, 23-285E5 and 23-286E5.
I'm looking for a copy of those for my archive...

-- 
Pete						Peter Turnbull
						Dept. of Computer Science
						University of York
Received on Thu Oct 15 1998 - 15:46:16 BST

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:31:26 BST