scsi voodoo on a quadra 700 with an 80 pin hd

[max1zzz]

Yeah, I misunderstood it. I should have specified that the drive I was using is an NP model of Fujitsu U160 SCA drive, that does have the jumper for Narrow mode. Am I correct to assume that my SCA U320 drives that aren't recognized in the same setup, and don't have the narrow mode jumper setting, would work in a narrow bus Mac with the upper bits properly terminated? @max1zzz's thread on terminating the adapters does have an example on terminating the upper bits on one of these adapters, if I recall correctly, so I might need to try that and see if my 72GB drives would work on Macs then.

My experience was that on drives that did not have any option for narrow mode terminating the upper bits would often get the drive recognised however even with correct termination some drives just wouldn't work on a narrow bus, and some would work on newer macs but not older ones (I have a 18GB drive in my PM 8600 that works fine in the PM but doesn't work on any 68K I have tried it on). I actually had quite good success with using U320/U160 SCA80 drives in 68K's but I did try and keep to the smaller, older drives. If you are ever looking to purchase SCA80 Drives to use in 68K's the 2.5" segate drives used in the IBM eServer's (i'm not sure of the Seagate P/N offhand) tend to work pretty well, I have a box of 15 or so of the 72GB versions that I am slowly working my way through as my 68k's need new drives and I am yet to find anything they don't work in.

One note about the way I terminated the adapters, the method I used really requires a 2.85v regulator, these (at least in the UK) are pretty hard to find and I ended up ordering the parts from china. You can make do with 2 or 3 diodes off the 5v / termpower lines or a 3.3v regulator but it's not in spec so could cause issues (it never did for me but as @trag points our in the thread it's not the correct way to do it)

On a side note - I do still have quite a few PCB's and parts for the terminated adapters I used to make so if anyone is looking for a terminated adapter feel free to drop me a PM, I stopped making them as I didn't think there was any demand for them after SCSI2SD came out

 

[Trash80toHP_Mini]

ISTR that some SCA drives were backward compatible all the way to the Mac's SLOW/Narrow SCSI implementation and some were not. Have vague recollections of the U160 standard requiring compatibility. It was dropped from the U360 standard(?) where some mfrs kept it alive and some put it down for the lame dog that it was. IBMs Savvios support narrow in 68k machines, but I've no experience with others.

 

[LightBulbFun]

On a side note - I do still have quite a few PCB's and parts for the terminated adapters I used to make so if anyone is looking for a terminated adapter feel free to drop me a PM, I stopped making them as I didn't think there was any demand for them after SCSI2SD came out

ah thats good to know  

I have a drive-less 9600 that one of these days I really need to sort out some sort of SCSI drive for at some point! (I use a PCI ATA card for most things I do with it, but that does not work if I want to mess with the more obscure OS's like OS X Server 1.x for example)

so its good to know there are a couple more options still beside the SCSI2SD (I would love a SCSI2SD but they bit hard to justify for me currently with how pricey they are, the V5.x's are not bad, but Ideally id want a V6 to make full use of the 10MB's SCSI bus in the 9600 and the V6's are like £100!)