Jump to content

New Internal HDD in Color Classic


Recommended Posts

I have a Color Classic that had a dead Conner 80MD hard drive. I was trying to replace with an IBM WDS-L160. Everything works OK when an external drive is also connected, and the system boots flawlessly from the new IBM drive. But when I disconnect the external drive, the system does not recognize the internal drive. I suspect I have a termination problem. I looked for a termination switch on the WDS-L160 drive, but failed to see one. Does anyone know how to solve my problem ?

 

Thanks in advance

Link to post
Share on other sites

Yes, that's the PCB. Looks like the block of jumpers in the front are for SCSI address, LED(out), and Autospin. The layout says that the terminator jumper should be in the back, near the 50pin SCSI connector. I just can't find it.

 

Capture2.JPG.06e9724284278dde6ed39ab102a24674.JPGCapture.JPG.4fc5e7b5567e939009b4022d5ae1ae5e.JPG

 

Link to post
Share on other sites

Look at the photo techknight posted.  Look at the top of the drive to the right.  You will see a small black dot among some pins.  This dot is a shorting block.  You need to use a pair of needle nose pliers to do this the easy way, but you can use your fingers.  You need to remove the short block (the black thing) from where it is now, to a different spot among the available pins.  What you are doing is telling the drive it is the master drive, and no drives are in the chain after it.  (or what ever your config calls for).

 

Others here can tell you where to move that small black shorting block.  All it is a bit of plastic with two holes in it so you can slip it across two pins.  Inside the black bit of plastic is a small copper wire.  When you slip it on between two pins it shorts them together, and this tells the drive what it's function is.

 

mraroid

Link to post
Share on other sites

Thanks mraroid. I am well aware of the use of jumpers, but no termination jumper exists on this particular block. Rather, the documentation says it should be closer to the SCSI connector (top right of the photo). I just can't find it

Link to post
Share on other sites

In this old IBM support doc for the IBM WDS-L80 & WDS-L160 (http://ps-2.kev009.com/ohlandl/IBM_HD/WDS_L80.pdf) there is a note that says "Not all models will have terminating resistors. In cases where there is no termination, an inline terminator will be required."

 

I guess you might need something like this:

 

SCSI 50pin Inline Active Terminator IBM 64F4774

https://www.ebay.com/p/1400296571

Link to post
Share on other sites
8 hours ago, techknight said:

Can that even be used? the CC I thought was an edge-connected HDD just like the LC5XX

A pass through terminator could be used in a CC, it’s a normal connector at the drive end of the internal SCSI cable:

291764CE-0C66-4B1A-866F-F6C583B0EE22.jpeg.7221b3c4851ef60681339539e5159ab4.jpeg

The other end of the internal SCSI ribbon cable is crimped to the motherboard edge connector:
 

087927AE-6E07-411E-AE86-90C31E5C7476.jpeg.2a1314f4ca11309ea2a23ca37e3c5ef4.jpeg

 

I would search around and see if such a terminator could be found cheaper than the eBay link I found, I really didn’t look to see if there are any cheaper options. 
 

Also compare the cost of any adapter with a drive that does have internal termination, like this:

https://www.ebay.com/itm/184429944114

Edited by Fizzbinn
Link to post
Share on other sites
8 hours ago, techknight said:

ok good. I knew it was one of the models that had those weird plastic blades for the SCSI connector. 

Yeah, definitely a good question. The CC seems to be a partial step to the 5xx full edge connector approach. I happen to have a parts CC dissembled and not packed away so It wasn’t too hard to grab some pictures that I thought might be interesting. 

Link to post
Share on other sites
  • 4 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...