Help on mixing SCSI-2 & SCSI-3 devices in chain required.

[x56h34]

I'll make this simple. Here's my SCSI-3 chain:



All the pictured devices are SCSI-3. I have an external ZIP drive (SCSI-2) which I'd like to add via the external 68-pin connector. How do I do this? What sort of terminator/passthrough do I need for this?

[Sparky]

Easy in theory .. bit difficult to get the bits in practice ...

You need an adapter that would convert your 68pin external SCSI-3 port to 50pin SCSI-2 AND that also terminates the high 8 bits of the SCSI bus ... then you'd attach your Zip with a SCSI-2 terminator on it (which would temrinate the lower 8 bits of the SCSI-3 bus)

You can get cables that do just this, they have a SCSI-3 connector on one end and a SCSI-2 connector on the other and somewhere in them they have the high 8 bit terminator.

Trick you need to pull off is finding a company/shop who will understand this and knows how SCSI works.

If you are in the UK, go to http://www.storagedirect.com I used to work there and it's where I learnt all about data storage, they know their stuff ... say Hi for me :-)

Regards

Mark

[x56h34]

I've just ordered an HD68M-DB25F, w/Active High Byte Termination adapter. Thanks a lot for the clarification! :-)

BTW, when I add this adapter to the external 68pin connector, will it from that point always terminate the rest of the SCSI-3 chain with no problems, or must I always have the ZIP drive w/ SCSI 2 termination attached as well?

[Sparky]

If you don't have your Zip attached then just remove you adapter and put a SCSI-3 terminator on the end of the chain.

Your adapter would only terminate the high 8 bits and not the low 8 bits ... which would leave you system unstable.

Or just leave the Zip attached forever.