Date: Thu, 23 Apr 1998 14:41:25 -0700 (PDT)
From: "Steven M. Schultz" <sms@moe.2bsd.com>
Message-Id: <199804232141.OAA22889@moe.2bsd.com>
To: jp@spektr.ludvika.se, pups@minnie.cs.adfa.oz.au
Subject: Re: RD54 problems.
Sender: owner-pups@minnie.cs.adfa.oz.au
Precedence: bulk

> From: Jorgen Pehrson <jp@spektr.ludvika.se>

> since my RD52 was a bit too small to fit 2.11BSD I now have found a RD54
> which will be a bit better... But when I removed the RD52 controller and
> inserted the RD54 controller my PDP can't find it. :(
> Under NetBSD in my uVAXII it shows up at 172150. But when I boot the PDP
> and try to "B DU0" it says: "Non-existant controller: 17772150".

	I have an idea what might be wrong.  I sure hope the M7555 has not
	been damaged.

> (Of course, there's no PDP OS on it. I just formatted the drive in my
> VAX2k with T 70 and remapped a lot of bad blocks. But that shouldn't
> matter, should it?)

	No, it should not matter.

 DU     0-255   CPU ROM MSCP (RA80/81/60, RD51/52, RX50, RC25, ...)
[...]

> Does that mean that it only recognizes RD51/52?

	No.  I just means that the RD54 came out after the firmware in the
	boot roms was written.  'MSCP' is the key word and the devices listed
	are just examples of supported devices.

> I've toggled in the boot code for the TK50 and booted the 2.11 install
> tape and ran disklabel on ra(0,0). And that yielded an:
> [..]
> Disk? ra(0,0)
> Trap in disklabel, bus error at loc 43470
> registers: r0=0, r1=0, ps=344, nps=340

	That instruction corresponds to 'clr (r3)' in the disklabel program.
	At that instruction the MSCP controller is being 'poked' to start 
	scanning its command ring.

> So I guess that something is wrong with the config of the RD54
> controller...

> Any ideas what could be wrong?

	Yes.  If the layout of the boards below is correct and you have a BA23
	box then the M7555 is in the wrong slot.

> Btw, the current boards in the PDP:

>      11/83 CPU
>      Mem board
> TK50 contr.    ra54 contr. (m7555)

	The first 3 slots of a BA23 are special.  Except for full high (quad)
	cards you can NOT use the "low" half.  The 'top' half is the A/B portion
	and the low half is the C/D part.  The first 3 slots of a BA23 you
	must use ONLY the A/B parts except for cards like the CPU.

	Thus the layout should be:

	11/83 cpu
	memory
	TK50	---
	M7555

	Note that the 'bottom' half of slot 3 is NOT used and is left empty.

	Slots 4 thru 8 you may use both the A/B and C/D portions but the first
	3 slots you are safer using only the A/B part.

	Steven