17 Jan
2006
17 Jan
'06
12:46 p.m.
Hi all,
I am working on the last peripheral device connected to
my 11/34, two RK07s. This will be my first experience
with RK07 drives, so I have a few questions.
I installed the RK611 in the system (in an expansion box)
and made sure that the UNIBUS is OK. The 11/34 starts, and
I can boot RT11 from DL0:. ".SH DEV" shows that the DM.SYS
driver is installed. However, after loading a pack the RT11
commands ".DIR DM0:" or ".INIT DM0:" report an error.
What error do you get. IIRC the RK07 pack can be formatted (this does a
low-level format of the data surfaces). You need to do that before
INITing in most cases.
I must say that the READY light did not turn ON on the
drive.
I switched the 11/34 OFF, because I think I need to take a
closer look at the RK07 drive itself first.
Here is what I did and saw.
I removed the metal cover at the top-rear side. Now you can
see the big magnet and the head assembly. I first checked
You can also swing the card cage assembly twards the rear of the drive.
Make sure you have the cables connected correnctly (IN and OUT are not
the same on these drives -- the controller must connect to an 'IN'
connector, the terminator to an OUT connector. Unless you have a
dual-ported drive, use the 'A' connectors, make sure you have the
interface card in the right slot of the cardcage, and press the 'A'
button on the front).
On the top of some of the boards are LEDs. The plastic cover over the
boards identifies them. What do they do at spin-up?
the "emergency retract" mechanism. When you
push down the
lever that locks the heads, and gently push the head assembly
forward toward the cartridge compartment, the heads are pulled
back as soon as the little microswitch is (dis)engaged.
OK so the 9.6V NiCd under the chassis is still good.
Then I loaded a pack and pushed the LOAD button.
After some 20 seconds the disk has spun up (I assume), because
the heads start to move.
You should hear the spindle motor start running. Mind you, if it wasn't,
you'd get some very nasty noises when the heads moved.
The heads first move at a moderate speed toward the
centre of
the cartridge (I would say a full travel), stop, and then move
back at that same speed, but not completely to the home position.
I think that is correct. The heads do a full seek to the inner guard
band, then return to cylinder 0.
Again, I *assume* that the heads detected track 0 and
stay there.
However, the READY lamp does not go ON. It could not, because
the lamp was defective :-) After replacing the lamp with a
checked-good lamp, I repeated the exercise. The heads show the
same movement, but the READY light stays OFF.
1. Is that head movement behaviour correct?
I think so.
I will try to make a movie of the movement this
weekend ...
2. What would the head movement be if the pack was bulk-erased?
I would think they'd go towards the spindle and then return to the
unloaded position as the drive wouldn't find any servo information at
all.
I've not tried this, so don't blame me if the heads run into the spindle
or something horrible, but you could unplug the servo head from the servo
preamplifer and try again. With no servo signals at all, you'd be
simulating a bulk-erased pack. Look for a change in behaviour.
IIRC there are 4 heads in the RK07. All 4 head cables plug into the
read/write board, but one of them has another connector coming from it.
That's the servo head. The 'connector' on that head on the R/W board is
just to anchor the cable, it's the end-of-cable connector that plugs into
the servo preamplifier that you might disocnnect.
3. Should the READY lamp go ON?
I think so, but it's been a long time.
An other thing I noticed.
As the 11/34 is OFF, there is no controller connected to the
RK07 drive. OK, it is, but not powered.
With the RL drives the FAULT lamp will be ON if the controller
is not powered. Is this the same for the RK07?
No, an RK07 will spin up and load the heads without a controller. No
FAULT lamp.
-tony