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SCM SwapBox SCSI<->PCMCIA Adapter

Trash80toHP_Mini

NIGHT STALKER
I found this thing in the ancient "Current Hacks" box . . . piccies coming up soon, meanwhile: SCM SwapBox

At any rate, there seems to be a lot more information around for these things than was the case 11 or 12 years ago, thanks to the Linux gang.

Best Description I've found, at least I think this is what I have:

http://www.murga-linux.com/puppy/viewtopic.php?t=75787&sid=e7263cfe7b1496f575507e9bdfd349d1

Interesting little adapter, 3.5" form factor and it appears to run off termination power . . .

Unless SCM snuck power onto some of the alternate ground lines, I've used dirty tricks like that . . . [}:)] ]'>

< reaches for continuity tester and camera >

Question: does 2-Channel SCSI mean two independent buses/controllers like I think it does? Dunno, doesn't sound very promising read that way.

If that's the case, is there any way to get this to work on a standard Mac SCSI Bus or an a Fast SCSI II Card using two IDs or on a JackHammer's Fast/Wide SCSI Bus?

Might I need to put two identical SCSI Cards into a system to make this work? That'd really suck eggs! :p

The controller seems very well documented: VADEM VG-469

 

Trash80toHP_Mini

NIGHT STALKER
Heh! Clever little rat 3@$^@&%$! Like I guessed, there are a whole bunch of the alternate ground lines that are NOT connected to ground.

Looks like the middle ground line on both connectors would be the power source, but there are still a lot of "ground lines" unaccounted for . . .

. . . nuts! :-/

Found another hit: MICROSYSTEMS SwapBox* Classic Dual slot supports Type Cards

. . . using image search helps a LOT sometimes. :approve:

 

Gorgonops

Moderator
Staff member
So... what is it that makes you believe that this device is SCSI in any way, other than a clearly confused discussion thread post where the person saying it uses "two channel SCSI" is undoubtedly solely doing so based on the device using SCSI-ish wide ribbon cables to connect the remote card slot carrier to the expansion bus? The chipset it's based on is explicitly an ISA-PCMCIA bridge device, with the datasheet saying *nothing* about SCSI, and if you look at other products based on they're all *also* ISA-to-PCMCIA bridge boards, or once in a blue moon it's found directly integrated on a device's motherboard.

The majority of ISA-PCMCIA bridge boards just mount a single slot so the card sticks out of the back of the host through the ISA slot cover, but I've seen remote dual-slot devices like this before too, usually in desktop small-form-factor 486/early Pentium era boxes. (I actually used one of the single-slot ones fairly recently to get a 16 bit Wavelan card running on an old luggable's ISA slot.)

SCSI to PCMCIA flash card readers do exist, but I'm 100% positive this isn't one of them. The pinout of those two cables is undoubtedly a completely proprietary arrangement which carries a buffered subset of the host's ISA bus (98 pins for the whole thing, so it would just fit on two 50 pin SCSI cables) to the slot adapter. (I'm assuming here that the Vadem bridge adapter is in the slot carrier, not on the ISA adapter card. Do you even have the ISA card portion? Alternatively of course the bridge chip would be on the ISA widget and the cables carry the necessary set of signals to support the two PCMCIA slots.)

 

Trash80toHP_Mini

NIGHT STALKER
I don't remember having the ISA Card, I'll give the place a good going over. There's a very good (bad?) chance it went down the Storage Room Whirlpool almost 8 years ago, so I'm not going to hold my breath.

Reading your post got me wondering how hard it might be do re-create that interface on a buffered, ChipSet enhanced upgrade hack for a PC Compatability Card? [}:)] ]'> It'd have to be one that's socketed, yet new enough to support the OS/drivers available for this bridge Chip. That'd be a very cool hack by itself, adding a full fledged Passive ISA Backplane would be even more so!

Be that as it may: I do have an external SCSI<->PCMCIA interface to try to get up and running, I'll post another thread about getting that one up and running on a Mac if I can't find the old one.

edit: I checked out that link, it sounds better than any other unit I've seen, using three IDs seems to very neatly sidesteps the LUN(?) issue I've been reading about with other converters.

 

Gorgonops

Moderator
Staff member
Reading your post got me wondering how hard it might be do re-create that interface on a buffered, ChipSet enhanced upgrade hack for a PC Compatability Card? [}:)] ]'>
If you do have the original ISA adapter board lying around somewhere you could certainly use it in one of those oddball old NuBus cards that have ISA slots... using it on anything newer that doesn't have the slot would be more of a problem. In principle most PC compatibility cards for a Mac probably have the signals for an ISA bus present on them somewhere, but that somewhere might be entirely inside a proprietary Southbridge IC. In any case, having it connected that way wouldn't make it accessible to the Mac, of course, unless you used some sort of client/server software setup.

In any case, what do you want this for? If it's to read PCMCIA flash cards on a pre-PCI Mac then the SCSI widget is probably your only practical choice. Or are you looking to host a PCMCIA peripheral, like a network card? If it's that, well, the SCSI widget won't help you either. I'm *pretty sure* that none of them are technically capable of supporting anything other than Linear Flash or (more usefully) ATA disk-emulating devices. (Which would include most flash cards over a few MB in size.)

 

Trash80toHP_Mini

NIGHT STALKER
I was studying PCMCIA bridges of three different types back when I was also noodling out the T-REX ASIC under the PCMCIA Card Cage for the PB 1400.

The one I can't seem to find had a Bridge Chip almost identical to T-REX and I was half hoping a lot of the pinouts would match up between them.

Now that prices are way down I've got a DOA 2300c MoBo and one of the comrades has gifted me with a certified DOA 1400 MoBo. Now I'm going to go at it from the other direction, desoldering every component leading to/from the Card Cage's interboard connectors on the 1400 MoBo and matching them up with the signals on the Duo's Docking Connector . . .

. . . doing the same for the traces leading from the clock multiplier legs of the Duo's Proc is the other side of this 10 years running SuperDuo hack. [}:)] ]'>

 
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