Ultra 320 SCSI

[spaceman88]

I recently got a hold of a bunch server SCSI drives (mostly Fujitsu MAT3073NC 73GB). Can these be connected to my A2000 so I can test/wipe them for sale. I don't know what's on them so I don't want to go to jail for selling top secret military info :-). The connector is not the same so I would need some kind of adapter, but would the Amiga be able to read/format these "newer" drives? I think it's an 80 pin connector, I tried a 68 pin drive with a 50 pin adapter a few years ago with not good results :-(.
Thanks

[ElPolloDiabl]

SCSI 1 , 2 and 3 are compatible.
Wide SCSI and ultra wide are not compatible with normal 50 pin.
But check with a google search.

[Zac67]

SCSI usually is fully upward and downward compatble, there are very few devices that can't be adapted. There are adapters for wide (68-pin) or SCA-2 (80-pin) connectors which will allow them to connected to your SCSI controller.

Usually those drives work right away yet some of them require full bus width termination - with one of those you'd need an adaptor with integrated terminator (or half-terminator if it's in the middle of the bus). Newer drives (U2W onward) provide no device termination any more.

Alternatively, you can change your cable to a wide cable and use standard terminators on that with a single wide-to-narrow adaptor for the controller (that's what I did) - you could even continue using an SCA backplane.

Oh yes, and make sure you use SE or LVD/SE terminators; LVD only terminators won't work.

[freqmax]

Don't ever mix single-ended and differential without converters in between.

[mechy]

These drives are fully compatible with the amiga with a 80 to 50 pin adapter preferably with high byte termination. they are LVD technically(not HVD which are incompatible).
most lvd drives will run fine in single ended(SE) mode.

Mech

[r.cade]

We end up with a lot of old SCA server drives in my company also.  I've tried to get them to work on the Amiga with adapters, but it's hit and miss.  

Some work, but aren't seen at power on (have to soft reboot).  
Some lock up the SCSI bus.  
Some work fine.  
Some work fine under 2.04 but lock up the SCSI bus when I soft-kick 3.1.

[spaceman88]

Don't ever mix single-ended and differential without converters in between.

Being the SCSI expert I am, I have no idea what this means:-(. I see $3.00 adapters on Ebay from China is there a chance of causing damage to my Amiga 2000? I have the Commodore SCSI card and a Quantum HD.

[Zac67]

There used to be a "differential" SCSI flavor with an extended reach and higher reliability in comparison to single ended (SE), the then standard. It was in limited use in datacenters and for special purposes.

When Ultra2 (U2W) emerged it introduced low voltage differential (LVD) to allow the higher frequencies required. The old differential mode was renamed to high voltage differential (HVD).

The point is, HVD isn't and can't be compatible with SE. Devices may very likely be damaged when connected to one another. There are converters/bridges to adapt the signals but they're extremely costly.

LVD devices on the other hand are predominantly compatible with SE (LVD/SE), with the SE mode limiting the bus to Ultra speed (20 MB/s for narrow, 40 MB/s for wide). Even if an LVD device at hand isn't compatible with SE nothing will smoke.

[magnetic]

I have also run 36gb and higher LVD drives (SCA connector converted to 50pin) on amigas.And obviously uwscsi converted to 50 pin works nicely as well.