[comp.sys.ibm.ps2.hardware] Expansion boxes for PS/2 series

sysmgr@KING.ENG.UMD.EDU (Doug Mohney) (07/27/90)

We have a model 70 which has 3 slots, but needs 4 cards (Ethernet, 2 slot
Pixelworks card, 5 1/4" adapter). Is there such a creature as an expansion
box a la the old IBM XT-type expansion boxes, either by IBM or 3rd party
(more likely 3rd party...)

austing@Apple.COM (Glenn L. Austin) (07/28/90)

sysmgr@KING.ENG.UMD.EDU (Doug Mohney) writes:

>We have a model 70 which has 3 slots, but needs 4 cards (Ethernet, 2 slot
>Pixelworks card, 5 1/4" adapter). Is there such a creature as an expansion
>box a la the old IBM XT-type expansion boxes, either by IBM or 3rd party
>(more likely 3rd party...)

As long as they have gotten around the problem of programming the slots in
the expansion chassis, it will work.  However, MCA REQUIRES access to each
card in the bus, and it wouldn't understand an expansion chassis too well...

-- 
-----------------------------------------------------------------------------
| Glenn L. Austin               | "Turn too soon, run out of room,          | 
| Auto Racing Enthusiast and    |   Turn too late, much better fate"        |
| Communications Toolbox Hacker |   - Jim Russell Racing School Instructors |
| Apple Computer, Inc.          | "Drive slower, race faster" - D. Waltrip  | 
| Internet:   austing@apple.com |-------------------------------------------|
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| Bellnet:    (408) 974-0876    |                who else would want them?  |
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gharding@sun.udel.edu (George Harding) (07/31/90)

I don't think an MCA expansion chassis is possible.  There is
however, an expansion chassis that gives 8 AT type slots that
goes in an MCA machine.  Can't remember offhand who makes it
but I could look it up if anyone cares.

jcmorris@mwunix.mitre.org (Joe Morris) (08/01/90)

In article <13035@sun.udel.edu> gharding@sun.udel.edu (George Harding) writes:
>I don't think an MCA expansion chassis is possible.  

I don't think it would be possible in the general case, since programs which
expect to be able to recover MCA setup parms wouldn't be able to get them
from CMOS, and boards which are MCA-configured wouldn't be able to get them
either if the board wasn't in a motherboard slot.

On the other hand, this wouldn't affect boards which have no MCA setup
parameters, or for which special drivers could interrogate the interface
card which supports the expansion chassis.

I've wanted this ability; my PS/2-70 has three slots and I'm already running
four slots' worth of extra stuff.  (One slot would have been used just to
provide an external connector for a Cumulus 5-1/4" disk.  I ran it out through
the cooling vents instead.)

austing@Apple.COM (Glenn L. Austin) (08/01/90)

gharding@sun.udel.edu (George Harding) writes:

>I don't think an MCA expansion chassis is possible.  There is
>however, an expansion chassis that gives 8 AT type slots that
>goes in an MCA machine.  Can't remember offhand who makes it
>but I could look it up if anyone cares.

I worked on a card to do this while I was in S. Calif.  The board was the
TransFormer/2 (sp?) from ADC in Huntington Bch.  I don't know if they are
still around or not (still waiting for that "call back in 2 weeks" from Jan
'89), but if they are, they may have even improved on it by now (or
discontinued it -- there are just some PC cards that have NO CONCEPT of how
to handle interrupts "correctly", they just toggle the IRQ low long enough
to get the attention of the PIC).

-- 
-----------------------------------------------------------------------------
| Glenn L. Austin               | "Turn too soon, run out of room,          | 
| Auto Racing Enthusiast and    |   Turn too late, much better fate"        |
| Communications Toolbox Hacker |   - Jim Russell Racing School Instructors |
| Apple Computer, Inc.          | "Drive slower, race faster" - D. Waltrip  | 
| Internet:   austing@apple.com |-------------------------------------------|
| AppleLink:  AUSTIN.GLENN      | All opinions stated above are mine --     |
| Bellnet:    (408) 974-0876    |                who else would want them?  |
-----------------------------------------------------------------------------

altman@sbpmt.cs.sunysb.edu (Jeff Altman) (08/02/90)

I just spoke with the people that make the Transformer II.
The way the expansion kit works is as follows.  There is a 
MCA board which is installed in the computer with a cable
to an expansion box.  The box contains 8 8-bit ISA slots.
For every board that you install in the kit you must know
what interrupt is being used, and all memory locations. 
this information is then installed in the PS/2 memory by
using the Reference Disk and an Option file which comes with
the box.  The installed board translates all calls via the 
interrupts and/or memory locations and sends them to the 
expansion box.  No DMA is supported.  

IT sounds nice, however, at $1600 for the box you might as well
buy a new machine.

- Jeff (jaltman@ccmail.sunysb.edu)