1 Dec
2011
1 Dec
'11
12:21 p.m.
On Dec 1, 2011, at 2:55 PM, Philip Pemberton wrote:
On 01/12/11 04:03, Tom wrote:
I'd be interested in it as well as interested in developing such a device; I was
thinking about it just yesterday because of my dwindling stash of real SCSI hard drives,
all of which are pretty noisy.
My primary "catch" with all this is the I/O, as usual; real 5v SCSI transceivers
are getting hard (and expensive) to come by, and the drive requirements are 48mA, if I
recall, which is a tall order for a lot of translation devices. Some of the signals are
open-collector, if recollection serves, but quite a few are actively driven. Not
impossible, certainly.
I come at it from an FPGA perspective, so something to bridge <=3.3v to 5v is
necessary. I would advise against what they recommended on the vintage-computer forum,
which is to use NOS or salvaged 5380, 53c90, 53c94, etc. chips; those are getting hard to
find in any quantity without resorting to scrappers.
Short answer: I'm interested in developing my own solution with an FPGA and a small
micro doing housekeeping and/or transaction-level logic. If you're interested in a
collaboration, I'm interested; otherwise, I'm going to make one of my own soon
because my disks are all dying.
- Dave
At 07:47 PM 11/30/2011, you wrote:
All this talk of SCSI has piqued my curiosity... maybe it's time for another
product...
Would anyone be interested in a device with the footprint of a 3.5in hard disk drive,
which allowed SD or CompactFlash cards to be connected to a SCSI bus?
Perhaps even with the option of emulating SCSI CD-ROM drives (including those pesky
512-byte block drives), or even multiple devices at a time ("this partition contains
a CD image and is SCSI dev 5, this one is a 1GB hard drive on dev 4, and this is a 100MB
read-only HDD on dev 6").
Obviously device IDs would be fully configurable (so you could make it pretend to be a
Quantum Bigfoot or Seagate Cheetah if you needed to). Multi-LUN and Multi-Device might
have to be (low cost) pay-for options, though... m88k Systems use standard SCSI and can use
anything up to 2GB without a
problem. I have DG/UX 5.?? on CD and 4.?? on Tape here.
As far as I know, the one we have uses standard SCSI (as opposed to
what? Diff?) as well.