UW-SCSI on SCSI2 bus ?? And 2.5"SCSI hd's size

[Jose]

Hi guys. Has anyone used an UW-SCSI hd on a SCSCI2 controler?.  Is the UW version compatible with earlier versions?  I think there are some adaptors around, are those just pin adaptors or do they have a small circuit to convert protocols?

The idea is to get a good 2.5" SCSI disk in my A1200. Maybe a 3.5" but I guess that won't be possible without modifiing the case.
I notced that the sizes of 2.5" ones are really small though, so I'm stuck anyway  :-x

[KennyR]

All SCSI devices should be backward compatible with older SCSI standards. Problem is that, AFAIK, UW-SCSI uses 64 pin and SCSI-2 uses 50 pin. You'll need an adaptor. But the protocol doesn't need converting.

My advice - get a cheap 2.5" IDE drive and an IDE->SCSI converter. It's cheaper and better than a SCSI one. Don't know if such a converter will fit with a 2.5" drive in an A1200 desktop case, though...

[Tesral]

My advice - get a cheap 2.5" IDE drive and an IDE->SCSI converter. It's cheaper and better than a SCSI one. Don't know if such a converter will fit with a 2.5" drive in an A1200 desktop case, though...

The controller native in the A1200 is IDE.  I am assuming that Jose is speaking about a SCSI card connected to the A1200 in addition to the IDE on the motherboard.

I have basically the same question.  With an adapter UW-SCSI controllers can handle 50 pin SCSI1 and SCSI2 drives, but can the older SCSI cards types 1 and 2 with 50 pins handle the 68 pin UW drives?  50 pin SCSI drives are getting hard to find for the old A4000

[jus]

it's surely possible to use a UW scsi drive on a Scsi2 adapter. I'm using one seagate 68-pin UW and one IBM 80-pin U2W drive on my draco with a 80 to 68/50 adapter right now. The problem you would have is that this adapter is quite large to fit in a 1200 case. The 68 to 50 ones are alot smaller though and I think you could use one of those. There is no circuitry at all on those adapter, it's just pin-to-pin conversion as the protocol is still the same. Another problem I can think of is that scsi disks tend to run faster than IDE ones and thus produce more heat. I have no clue about the 2.5" ones though, as I have never seen one.


Justin

[Jose]

Right, thanks for the info. Haven't been much on the net ultimately and so the late reply.
NOw I just need to find a good SCSI drive for my A1200.
The Blizzard SCSI kit, wich is what I have,  can handle around 10Mb I'm told, (or is that 10MB :-o ), so it should be more than enouph for a CLassic A1200:-D