• Please review our updated Terms and Rules here

DB37 CDROM port

S

Syntho

Experienced Member
Joined
Feb 23, 2022
Messages
83
This old 386 I acquired has a CDROM and it has two peculiarities (to me). One is that the CDROM attaches to an ISA card via a ribbon cable, which is normal, but the ISA card has a DB37 port on the back of it and it says "CDROM Interface Port". Is this for connecting yet another, external CDROM to the PC? I want to say it's a SCSI looking port, but a google search led me to believe that it's a serial port.

The other thing is that the CDROM connected to the ISA card via ribbon cable has " CD Caddy" on the front, so it probably takes those clear cases that CDs go into. I guess I'll have to find some of them on eBay ad hope it's the right kind.
 
I have a couple of old external CD-ROM drives using a d-sub connector. Goldstar and Hitachi interfaces used that, for example.

What's the brand of the drive and card you have?
 
Just took the drive out and it's a Sony CDU535-01. The Host Card is a little difficult to identify. It's a PROCOM TECHNOLOGY, and I can only find something on the back that says BD0025, and close to it, 2991. Other than that, the sticker by the port says LB00037.
 
Scsi uses db37 sometimes... Is the cdrom scsi? Total hardware 99 doesnt say, but says it has a termination jumper. Im going to guess its scsi...
 
This rings a bell vaguely.
Is the internal ribbon cable 34 pin or is it full size IDE?
Does the ISA card have next to the external DB37 a 3.5mm jack?

I want to say this is either one of Sony's proprietary CD-Rom drives and interface boards which supported external and internal CD drives, or it's going to be a really, really early Sony IDE CD-Rom drive.
Photos would be helpful.
 
I have a few of those 34 pin sony slot loading drives, never seen a card for them tho with external connector. They always just got bundled with a soundcard. Could be but then why the termination in total hardware? Thats a scsi thing, but who knows what Sony did... anything is possible with them! LOL
 
Just took the drive out and it's a Sony CDU535-01
Click to expand...
Ok, that one. ;) Very old drive. Pictures of the drive and card can be seen here:

www.kijiji.ca

Sony Caddy CD-ROM Drive CDU-535-01 | CDs, DVDs & Blu-ray | St. Catharines | Kijiji

Sony Caddy CD-ROM Drive CDU-535-01 VERY RARE ITEM in Working condition - One caddy is included - PDF Instruction manual - DOS/WIN/OS2 drivers - $398.00 - Call or Text 289-990-6060
www.kijiji.ca www.kijiji.ca

It's using a proprietary interface and the port on the card is for an external drive.

Note that all Sony CDU-5xx drives have leaking surface-mounted caps on the pcb. Like with the Amiga 600/1200/CD32, the question is not if they leak, but how much damage there is already. I've serviced about 10 of these drives so far and all had severe damage. If you want to save the drive, replace the caps as soon as possible. It's unlikely that the drive even works in its current state anyway.
 
Last edited:
See the attached pictures. The manual states that there is a Host Card from Sony called the CDB-240. I definitely have something different. If there's a custom driver for it, it's still on the hard drive I inherited. It still has the original DOS 5 install from 1991 or 1992 on it, so I can probably copy it before it's lost.

Now I'm curious about the external port on the card. I guess there's a special cable for connecting a Sony external CDROM drive to it or something.

The manual also states to use OPA-1011 caddies for discs. I'm not sure if there are generic/interchangeable caddies for it.

I want to get this up and running so I'll take a look at the caps and buy some new ones soon.
 

Attachments

  • 1.jpg
    1.jpg
    1.4 MB · Views: 6
  • IMG_0042.jpg
    IMG_0042.jpg
    1.1 MB · Views: 12
  • 454.jpg
    454.jpg
    1.1 MB · Views: 13
  • 23.jpg
    23.jpg
    1 MB · Views: 13
  • Untitled.jpg
    Untitled.jpg
    675.9 KB · Views: 10
  • 4.jpg
    4.jpg
    711 KB · Views: 8
  • 3.jpg
    3.jpg
    1.5 MB · Views: 6
  • 2.jpg
    2.jpg
    740.2 KB · Views: 7
The manual states that there is a Host Card from Sony called the CDB-240. I definitely have something different.
Click to expand...
Yes, these cards were made by others, too. That's why the manual only recommends the Sony-branded card (of course ;))

I guess there's a special cable for connecting a Sony external CDROM drive to it or something.
Click to expand...
Should be a 1:1 cable. I have this one in my collection which uses the same Sony mechanism as well. Pretty sure that's one of the external drives you could connect to the card.

IMG_20180323_194044302.jpg
 
Timo W. said:
Note that all Sony CDU-5xx drives have leaking surface-mounted caps on the pcb. Like with the Amiga 600/1200/CD32, the question is not if they leak, but how much damage there is already. I've serviced about 10 of these drives so far and all had severe damage. If you want to save the drive, replace the caps as soon as possible. It's unlikely that the drive even works in its current state anyway.
Click to expand...

Take a look at a section of the surface mounted caps. It's got a little of the green goo on the joints. I've had other gear that had this exact same problem. Surface mounted caps seem to be bad about this.

It would be great if I could save the drive but I don't know that it's going to be worth the effort. I've never soldered surface-mounted caps before and I probably wouldn't know what else to test and replace. Hmm... I still would like to do what I can to save it though. It's a cool piece of gear.
 

Attachments

  • 34343.jpg
    34343.jpg
    544 KB · Views: 9
but I don't know that it's going to be worth the effort.
Click to expand...
That always depends. If this isn't the CD-ROM drive you had in your first PC, nor are you collecting early CD-ROM drives, then it's probably not worth the trouble for you. I mean, you can just install a different, working drive into the 386 and you are good to go.

In any other case however, I would certainly try to save the drive or give it to someone who takes care of it. As for replacement caps, I always use tantalum ones to replace these. But those are quite expensive, even if you only need 9 for the whole pcb.
 
btw, just checked my notes about the external drive I showed above and I've written: uses a proprietary D-SUB 37-pin Goldstar Interface "R420"
 
Syntho said:
It would be great if I could save the drive but I don't know that it's going to be worth the effort. I've never soldered surface-mounted caps before and I probably wouldn't know what else to test and replace. Hmm... I still would like to do what I can to save it though. It's a cool piece of gear.
Click to expand...

It's an old trick the mac people used before they realized recapping was the solution but sometimes removing the board and washing it to remove the leaked electrolyte gave you a little bit more life before you had absolutely no choice to recap. Gives you a good chance to test it before committing the parts and time.
 
There are tons of variable resistors on the pcb. I would not recommend "washing" it. If you accidentally change the value of any of the variable resistors, chances are very low to ever get it working again - unless you have the service manual and a scope. If you think laser adjustment with BIAS, GAIN, and FOCUS is complex, good luck on those old drives with 3 times as many adjustments. ;)

If anything, only clean the sections with leakage. But I don't see the point. Either go for a full repair or leave it as is.
 
I've been collecting information on SLCD and the other pre-ATAPI interfaces for a while
since information on them is pretty much all gone now.

you can find some information under http://bitsavers.org/pdf/sony/cdrom

also, some reverse-engr i've been doing on a simple ISA CD-ROM interface board
with information on the SLCD protocol.

 
Last edited:
I've been collecting information on SLCD and the other pre-ATAPI interfaces for a while
since information on them is pretty much all gone now.
Click to expand...

Nice. Below are pictures I made from a CDU-541-22 while servicing it. Feel free to use them. That drive was used in the Apple CD SC Plus.

IMG_20160401_110948_525.jpg IMG_20160401_111003_179.jpg IMG_20160401_111016_266.jpg IMG_20160401_164439_979.jpg

Let me know if you are interested in pictures of other (non-Sony) drives as well. I collect early CD-ROM drives (both internal and external ones) and have quite a few of them. Some are even on display in my museum.

IMG_20211111_102112438_HDR.jpg
 
Will just about any type of caddy work with this cdrom? Don’t want to buy the wrong one.
 
You must log in or register to reply here.
Back
Top