View Full Version : CBM (Commodore) D9090 Hard Drive Issue

December 6th, 2005, 05:39 PM
[copy from my orig. post to cctech on classiccmp]

I leave the unit powered up for a good ten minutes before turning on my known-to-work Commodore B128. The expected drive initialization lights flash and the system sits waiting for action while the top light shines green, the bottom light is off. Here are the things I have tried:

?ds$ - returns CBM DOS 3, etc. message
open 15,8,15
print#15,"i0" [top and bottom lights shine green, drive sounds spinning, never completes.]
close 15

NOTE: The first time I run these commands the READY prompt returns to the screen and I can continue working, even though the drive lights perpetually shine green and the drive spins. If I do repeat this set of commands however I will freeze up the computer and I am forced to hard boot the B128.


header "degnan9090", d0, i01

The "are you sure?" message appears and I can initiate the drive format. Both lights shine green. The B128 freezes up. Because I have a Rev B ROM, I expect that it will take less than 3 hours to format the drive. In my testing I finally aborted after 10 hours. I know from experience that when a header command is issued, control returns to the B128 (or whatever computer) while the formatting is happening on the drive.

dcleard0 - does not appear to move the drive heads.

It seems like the heads are not moving and that's the problem. I do not hear "head moving noises"

Any suggestions?

Bill D
Wilmington, DE

December 6th, 2005, 08:24 PM
btw - I have kind of concluded that the hard drive is bad, and I think that it's easy enough to swap out so I might as well try. I have a Tandon model 603s in there now. What other drives are compatible with the Tandon model 603s?

TM 603S : 6 : 153 : 128 : 153

I read someplace that the controller of the D9090 can handle any similar hard drive as long as the heads are of an even number.

January 15th, 2006, 12:16 PM
As I am packing up (live near Annapolis, MD) for the move to FL, I might not as yet packed the 9090 reference guide, and or manual.

(1) The 9090 formats to 7.5 megs. All were Tandon 15 meg drives.

The worst thing you can possibly do has been done. To issue a format command when your not sure what your doing, is dangerous.

(1) Turn all rooms lights off.
(2) Power up the computer.
(3)Power-up the drive and WATCH the lights. Count the flashes! It will flash a specific number of times.
(4) Repeat step 3, and verify the flashes.
(5) Issue the catalog command.
The drive should spin, the lights should flash (repeat command). Maybe a message will display.

(6) Some PET-IEEE cables do not have the Keyway. It is possible such a cable could be flipped over and plugged in wrong.

I have several PET drives here that I am packing up. It's best to email me direct at wishbringer2001@hotmail.com

January 15th, 2006, 01:55 PM
I have been very careful, I now have the manual.
If anyone can help...I need a new drive. Tandon 603s.

January 17th, 2006, 01:05 PM
These are ancient drives. The mechanisms are more than 20 years old.

The original description of the drive lights (steady green and the activity light out) really meant the drive was 100% functional at that time. While it was awaiting a proper command you send it a format command (logic escapes me), and then while commanding it to format you decided enough was enough and interrupted the process.

Suggest you try the catalog command.
Suggest you check the drive cables (both 20 and 34 pin on the drive and the controller board.

January 21st, 2006, 12:58 PM
I may have been a little caustic with you. I really do not mean to belittle you.
Now that the amenities have been observed, let's get down to it.

I am definitely well versed in the 9060-9090 drives, having owned and operated a BBS with several 9090,9060,8250,8050,and MSD-dual Pet drives. Having said that, let's not assume I am conjure up a remedy mentally.

I asked several questions, and did not get any reply.
The Tandon 603s drives are MFM drives. (Flat 20 and 34 pin edge card connections on the drive).

I have 2 working Seagate ST251 MFM drives on the shelf right now, but will start packing up that room the middlw of next week. The ST 251 is 40 megs. The above ST251's were part of CBM2090A card and cables setup I made for a children's center years ago that had 1.3 A2000's. :D