Subject: Re: port-mips is a mips-CPU list, not a MipsCo port
To: Jonathan Stone <jonathan@DSG.Stanford.EDU>
From: Carl S Shapiro <cshapiro@sparky.ic.sunysb.edu>
List: port-mips
Date: 02/23/1997 05:10:56
> That said, someone *is* working on a port to a Mips Magnum 3...
> I don't know how like a Magnum PC-50 that is. 

Absolutly nothing like it!

> What *is* a Magnum	PC-50?

Well... way back when, Microsoft designed an R4000PC based machine to
run Windows NT, it was called the "Jazz".  MipsCo later purchased this
design, changed it a little, and sold it as the "Magnum".  The design
didn't differ much from the original Jazz, except for a few
modifications to the board layout and to add support for the R4000SC.
After the Magnum shipped, Microsoft bought a number of these boxes to
replace the machines based on the original Jazz design.

The Magnum is a really grotty piece of hardware (no suprise Microsoft
engineers) with a weird bus controller that allows one to graft an EISA
bus onto the MIPS local bus.  It also uses a proprietary graphics
controller which is extremely difficult to find.  The machine had the
ability to boot in either little endian (Evil Empire) or big endian
(RISC/OS) modes.

What is really unfortunate is the Mips had their own R4k based machine
under development ("Aftershock") which was based on the TurboChannel
bus.  I guess they dumped it because this would have forced them to
rewrite all of the HAL's for the machine.

Most every ARC machine is a close derivation of the Magnum design
(i.e.  Acer Pica, NEC Express, etc).  The only non-Mangum based
machines I know of are the Siemens SN series of SINIX workstations, the
DeskStation Tyne, and the SMP {NEC,NetPower} boxes.  Given that the
Acer Pica is just a repackaged Magnum, I am pretty sure MipsCo Mangum
support would not be too hard. 


Carl