Eric,

There's a very nice page on the KA650 at:

http://www.telnet.hu/hamster/dr/ka650.html

and much of that info applies to the 655 as well.

On 28 Feb 2000, Eric Smith wrote:

> I have a KA655 in a BA123 with an RQDX3 and RD54.  (The machine was
> originally a VAXstation II/GPX, but I pulled the VCB02 and replace the
> CPU.  Eventually I may put the VCB02 back in.)

A mongrel now, eh?  Well, I've a few of those.

> When the machine first comes up, SHOW DEVICE reports the drive as an
> RD51.  After several resets, it finally decides that it's an RD54.
> 
> Is this normal?  Or is something broken?

I haven't had this experience myself, but there was some traffic 
recently on comp.os.vms about a guy who had an RD54 that thought
it was an RD53.  It might have to do with how it was originally 
formatted.  Somebody help me here.

 
> Is there a console command I can give that will cuase the system to
> not attempt to autoboot?  Right now I've got that by giving it a
> SET BOOT with a bogus device name, but surely there's a better way.

See the above web page, but generally just flip the halt enable 
switch to the "up" position (dot in circle).
 
> Is there a way to abort an attempted boot?  When I first fired up the
> box, it was always trying to boot from XQA0, and I had a difficult time
> getting a command prompt.  I'd hoped that the halt switch on the front
> panel would do that, but it seemed to only make it run the power-up
> diagnostics in a loop.

If the diagnostics are going in a loop, then you have the middle knob
in test mode (T in circle).  Flip it to run mode, which is the arrow
picture, the top position.
 
> If I add more drives, do I need to install more front-panel inserts for
> them?

Not necessarily, but you won't have control then as to whether they are
writable or offline.  I believe the default is online, writable.
 
> Can a BA123 handle three RD54s, a TK50, and an RX50?

The TK50 only depends on the presence of the TKQ50 controller.
The RQDX3 controller can handle 4 MFM/RLL drives, of the special
types that it knows about, and the RX50 counts as two of those.
However, those controllers are cheap to come buy, and you can 
stick a second one in, and jumper it to the secondary disk controller
address.  They can also coexist with KDA50 or KFQSA controllers.

Doug