SCSI adapting SCA-80 to IDC50

[velocityg4]

I've been trying to get a WD45FH-00ASA0 drive functioning in a IIcx. So far all the jumper settings on the drive and SCA-80 to IDC50 adapter have failed to get it recognized on the computer. Apple HD SC (patched) doesn't see any SCSI devices when it is connected.

The SCSI controller is good. An old Apple 5.25" 160SC works fine.

I assume the drive is good. It spins up. It was new old stock. I bought a few of them. All spin up fine but none are recognized. Unfortunately I can't find any manuals for the drive. I found one for another model but some of the jumpers are different.

The adapter is unknown. It is new. I can only assume it is good.

Could this be a termination issue? When I test with the old Apple 160SC or Apple 300i CD ROM. I can see and use external SCSI devices. When using the adapter. External SCSI devices are not detected. The same occurs if no internal device is connected. Unfortunately I can find no way to terminate the drive. I don't know if it built in or not. I've ordered a two device IDC50 cable and an internal terminator. But those won't be in until Monday.

I've tried playing with the jumpers on the adapter and hard drive.
- Force SE: Hard drive won't spin up
- SCSI ID 0: Tried on the drive, adapter and both. No effect
- Syn: Tried with and without jumper on adapter

Pictured is the drive and adapter at their factory jumper settings.

 

[MacTech68]

Caveat: I've never used an 80 pin drive as a replacement for a narrow, slow SCSI drive.

However, according to this document:

Wayback Machine

on the last page it shows that the WD45FH does not supply Termination Power to the bus, and has a 'Force Single Ended' and a 'Disable Wide' jumper - which I would propose should be jumpered in order to operate on the IIcx.

Further, the table at the end of the document notes that the drive does not have internal termination. This means one should be added to the cable after the drive (at a very short distance).

I can't see in your picture of the drive which jumper would 'Disable Wide', though 'Force SE' is clearly present.

Did you get any instructions for the adapter ? I'm not familiar with some of those jumper notations either.

EDIT:

Spec Sheet for WD45F series:

Wayback Machine

 

[velocityg4]

The default jumper setting on the hard drive is D TRGT INIT. Which should disable target from starting the negotiation for bus width, bus speed, and synchronous/asynchronous data transfer. Only the initiator will start negotiation.

Force SE just keeps the drive from spinning. Although my understanding is this should auto negotiate to SE if the jumper is not in place.

I couldn't find the Western Digital Quick Installation guide for this drive or any 80 Pin WD. But I did find one for a 68 Pin drive. Which at least explains some of the jumper pins. Although others described in the guide don't exist on the 80 pin model (ie Termination). I'd expect the WD Quick Installation guide for another 80 pin model would share the same jumpers or at least be much closer.

I did get a response from the seller who contacted the manufacturer. Confirming that SCA 80 drives typically do not have termination. Since they'd typically have been used in servers with hotswap bays which took care of all the settings. That I would need to place a terminator at the end of the internal SCSI chain. Which is the likely cause both the internal and external SCSI chain failing when the drive is connected.

My two device cable arrive first. I'll just plug my Apple 300i in at the end to provide termination. Hopefully the new drive will work.

Here's the instructions which came with the adapter.


Attached are the guides I found for 68 pin drives and a more extensive guide for the adapter. (PDF Files)

 

[MacTech68]

The only install guide I could find was a generic from February 2000 that suits 50, 68 & 80pin.

https://web.archive.org/web/20000831025755if_/http://www.westerndigital.com:80/acrobat/SCSI-IG.pdf

Termination might be the problem. I've always believed that the tray loading 300i Plus termination jumper was for supplying or not supplying Termination Power to the SCSI Bus, rather than enabling termination.

 

[velocityg4]

Just an update. I got it to work. While some of the 80pin drives play nice with a 50pin terminator. This one doesn't. I had to get an 80 to 50 pin adapter with built in termination. To properly terminate the extra pins. The only jumper setting I needed on the drive itself was Force SE. On the adapter I used sync and delayed start.