Re: Crazy cross-MIPS-boards stunts possible?

On Thu, 3 Dec 2020, Maciej W. Rozycki wrote:
> embedded applications.  A newer ABI (NUBI) was outlined to phase out the 
> old o32/n32/n64

What version of the MIPS ISA did n64 come along, was that MIPS IV ?

> Then there were further attempts with the nanoMIPS architecture,

nanoMIPS... never heard of that. Cool. I see notes about qemu deprecating 
support for it and not too much else.

> including a functional toolchain, but it all has gone once the latest 
> incarnation of the owner of the architecture went bust earlier this 
> year.

Sounds like an Amiga story.

> The Malta was designed by MIPS Copenhagen

In general, thank you for that interesting writeup on the Malta.

> the remaining board material, including in particular blank PCBs, was 
> moved to the US. It was then used to assemble more boards sometime in 
> 2000s.

Hmm, I used to work near LSI on Garden of the Gods in Colorado Springs. I 
wonder if any of the components or assembly touched that site.

> Given the persistent demand around 2008 a new, software-compatible 
> variant was designed, called Malta-R,

Was that by the same group of folks or a new company? I assume all this 
stuff was for profit and not any kind of open-hardware thing, or was it?

> You may have a hard time finding one that someone wants to get rid off, 
> as usually with this kind of stuff.

Understood, but sometimes patience pays off. SGI MIPS hardware has 
fluctuated over the years of the used market but the general trend seems to 
be upward on price and downward on availability.

> Most everyone seems to be using QEMU rather than actual Malta boards.

I've already started to jump on that bandwagon. I just built the latest 
qemu from git and I'm ready to do an install this weekend.

> NB a completely new design using contemporary components and interfaces 
> was of course also made, around 2009, which was called SEAD-3.

I had to look that one up, too. It looks almost like a homebrew project.

> The SEAD-3 has an FPGA rather than a core card, so (unlike the Malta) it 
> always has a soft CPU core.

The Vampire "68080" in my Amiga 500 is the same idea. Super-fast 68k clone 
with some SIMD features nicely integrated. I think they made a standalone 
Vampire, now, too. Won't run NetBSD though because of some MMU silliness.

> They are development boards after all, so they had to suit whatever the 
> customer's requirements were.

Bi-endianness is still cool and still not widely available enough, IMHO, 
even if you old  MIPS dogs think it's old hat. :-)

-Swift