[rescue] zuluscsi wide sca80 or scsiknife sca as replacement to hd in sun ultra 60

[Dave McGuire]

On 5/26/26 04:40, Mark Benson via rescue wrote:
> I think the whole “it’s not an emulator” argument misses the boat completely on why people refer to BlueSCSI or ZuluSCSI as an “emulator”, aside from that being a catch-all (often incorrect) term for “it does old stuff with new stuff” phrase.

   Right.  But around 1998 or so I put an 18GB drive in my SPARCstation 
to replace a 2.1GB drive.  That was doing old stuff with new stuff too, 
but nobody in their right mind would call that an "emulator".

> The reason it’s referred to widely as an emulator is *not* because it’s “emulating SCSI” because, as people gave often pointed out, it does not. It is an actual SCSI device capable of handling multiple IDs and LUNS. That’s in the spec.
> The emulation part is that the device is capable of storing and behaving like multiple actual devices like hard drives, optical disks, zip disks, NICs, printers (yes that’s in the works), etc. to “emulate” the presence of a device, complete with it’s original device identifiers if required (hi, yes DEC, Apple we see you). So it’s emulating the *devices* not the SCSI part.

   That I can agree with, as long as we don't say it's emulating a hard 
disk drive.  Because it just plain isn't.

> Calling it a SCSI SSD is misleading also as it has none of the wear levelling or flash management features a drive we consider to be a modern SSD does.

   What people assume all SSDs do because SOME SSDs do isn't really 
relevant here.  The SSD that I had on my Sun workstation in the early 
1990s was implemented with DRAM chips.  It didn't use (or need) wear 
leveling or flash management.

   But as pretty much all SD cards do that wear leveling internally, the 
ZuluSCSI (etc) boards don't need to implement that functionality.  So 
the combination of a ZuluSCSI board and a MicroSD card does in fact 
implement wear leveling and flash management features.  None of which 
has anything to do with SCSI, though.

> I realise “SSD” literally means Solid State Device or Solid Stare Drive (technically correct as it uses commodity solid state media) but it ignores the other utility features that the modern implementations of the BlueSCSI/ZuluSCSI offer. SCSI2SD was much closer akin to a SCSI SSD as it was using almost block-for-block mapping. These do not. They use free floating files on a FAT32/exFAT card, and go beyond “just storage”.

   Agreed.  Yeah I viewed the older SCSI2SD card as essentially a SCSI 
bus to SD interface translator.

> It’s not a SCSI emulator. It’s a SCSI device with a built in *device* emulator.

   Yes, I agree with that, again as long as we don't say it's emulating 
a hard drive.

> Also, on balance, very few people care, it’s a thing that does SCSI and I for one just appreciate it exists.

   Me too.  But not only am I an engineer, I am frequently in the 
position of educating people (when I'm working at the museum) so my 
terminology had damn well better be correct.

              -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA