On Wed, 19 Aug 1998, William Donzelli wrote:
> Captain Napalm wrote:
> > Another problem is that nearly each machine used a unique MIPS processor
> > which were more source compatible than binary compatible. Well, that isn't
> > exactly true---the opcodes were the same, but each MIPS processor has a
> > slightly different pipeline and code compiled for one MIPS chip (say, the
> > R3000) might not work correctly (or work at all) for another (say, the
> > R10000).
Code compiled for the MIPS-I instruction set (for the R2000/R3000) should
run on later MIPS-II through MIPS-IV machines. Running old MIPS-I code on
an R10000 is extremely inefficient, but it works. SGI's change in object
file formats (from COFF to ELF) and use of several different ABIs (o32,
n32, n64) in their recent OSes seems to cause more compatibility problems
than the differences between the MIPS chips themselves.
> I think the IRIX support for the Power Series (or probably most of the 4D/
> machines) died around v5.0.x.
IRIX 5.3 will run on a Power Series (or any other 4D) machine, as long as
the graphics subsystem is supported. GTX, VGX, and Reality Engine should
all work. 5.3 uses more memory than the earlier versions, but I run it
relatively comfortably on a 4D/35 with 32 MB of RAM. IRIX 6.x will not
run on the 32-bit R2000/R3000 processors.
I don't know if the Merced/NT announcement a few months ago is
responsible, but there seems to be a glut of SGI gear on the used
equipment market right now. Hobbyist licenses for old versions of IRIX
would be great, if SGI could be convinced to do such a thing.
If you haven't found it already, there is some useful information about
the 4D series machines (including connector pinouts, specifications, and
power requirements) at
http://www.geocities.com/SiliconValley/Pines/2258/4dfaq.html
--
Scott Ware ware_at_xtal.pharm.nwu.edu
Received on Wed Aug 19 1998 - 12:50:20 BST