PDP-11/94-E

Rod Smallwood rodsmallwood52 at btinternet.com
Thu Jun 2 15:18:46 CDT 2016



On 02/06/2016 19:19, Noel Chiappa wrote:
>      > From: Rod Smallwood
>
>      > Needless to say all of the locations I examined came up filled with
>      > zeros.
>
> Device registers will be in the range 17760000-17777776 (although toward the
> top you'd mostly see CPU registers). The RX02 controller (RX211) should be at
> 17777170-6.
>
>      > Although the monitor display says Unibus system. I suspect what I have
>      > is a CPU used in a Qbus system with a hacked monitor and boot eprom.
>
> Hmm. Well, the same physical board should work in either system (/93 or /94)
> - and I suspect the ROMs check to see if there's a UNIBUS adapter (KTJ11)
> there, and declaim the CPU board as a UNIBUS or QBUS, depending. (I.e. I
> would wonder if there are separate QBUS and UNIBUS ROMs.)
>
> That's because I have this bit set that there aren't separate /83 and /84
> versions of the KDJ11-B for the two busses, and I would think that the /93
> and /94 would likely be the same. (I should read the -B and -E manuals to
> confirm that.) And I don't think there are separate part numbers for
> KDJ11-E's for QBUS (/93) and UNIBUS (/94) systems.
>
> But I'm not familiar with the ROM contents, so I can't say for sure. When
> debugging broken hardware, I tend to ignore boot/diagnostic ROMs anyway, and
> stick to simply what the hardware does (as seen via ODT), as that's a) much
> less complex, and b) fully documented. (I don't know of any ROM listings, and
> I'm not about to disassemble them!)
>
> So if you can't see the RX211 registers from ODT, let me know, and we'll
> figure out what to try to see if the KTJ11 is working properly.
>
>      > For whatever reason they managed to disable the unibus  I/O
>
> I'm not sure you can (in hardware terms, that is - and clearly if there's no
> way to do it in the hardware, the software cannot do so)... although it could
> be broken.
>
>      > I have what I believed is a working 11/83 in my computer room
>      > I'm going to try my processor in there
>
> There's a section in the /94 maintainence manual (EK-PDP94-MG-001, available
> online) about upgrading an -11/84 to an -11/94; you might want to read that
> to see if there are any gothca's in terms of the cabling, etc. (The console
> cabling will be an issue, of course, since the KDJ11-B and KDJ11-E use
> different console connectors on the board - I'm talking about the other
> cables.)
>
> But AFAIK the KDJ11-E (/93 and /94) is a compatible upgrade to the KDJ11-B
> (/83 and /84), so your plan should work.
>
> 	Noel

OK Here's what I did

1.  Jumpers on underside of board all on

2. KDJ11-E in first slot

3. APM in second slot connected to CPU

4. nothing in slot 3

5. Unibus Control card in slot 4

6. RX02 Control card in slot 5

7 Bus Grant in 6,7 and 8

8 Bus term and MLM in slot 9

Turn machine on drop into ODT key location in and  press / get ?
same  for all of the others.

Rod



More information about the cctech mailing list