When Digital Systems Research Lab started in 1984 after the implosion of PARC CSL, the first machine we built was a 68000 (68010?) version of the Firefly multiprocessor.  We were able to score some MicroVAX II chips soon enough that we redesigned using those, which was, ahem, more politically astute at Digital.

Only a few 68K versions were built.  The Firefly supported a Unix/Ultrix system call interface but otherwise used unrelated software.

(Funny story about close(2).  The initial version raised a Modula-2 signal when you tried to close an already closed file, which was very slow.  The OS folks, unused to Unix, had no idea that was something you do all the time.)

Regarding the SUN-1 design, I had heard a rumor that it was designed using TTL “typical” propagation delays rather than worst case, and as a result was fairly flakey.  This caused me to not join sun <very> early since Eric Schmidt had the office next to me.  One of my many life mistakes.

-Larry

> On 2021, Apr 9, at 1:01 PM, Dan Cross <crossd@gmail.com> wrote:
> 
> On Fri, Apr 9, 2021 at 11:35 AM Paul Ruizendaal via TUHS <tuhs@minnie.tuhs.org <mailto:tuhs@minnie.tuhs.org>> wrote:
> > On 09/04/2021 11:12, emanuel stiebler wrote: > You're comparing a z80 SBC running CP/M? Or are you thinking of 68000 SBCs? 
> 
> Z80 CP/M machines were still competitive in 1981-1983 (Osborne, Kaypro) 
> 
> > I've never seen a 68k SBC. Have I missed out something along the way? Is there a community for 68k SBC's? Kind regards, Andrew
> 
> There is an active community around DIY 68k SBCs these days. Some representative examples:
> 
> https://www.eejournal.com/article/wallowing-in-68k-nostalgia/ <https://www.eejournal.com/article/wallowing-in-68k-nostalgia/>
> https://www.ist-schlau.de <https://www.ist-schlau.de/>
> https://www.bigmessowires.com/category/68katy/ <https://www.bigmessowires.com/category/68katy/>
> https://github.com/74hc595/68k-nano <https://github.com/74hc595/68k-nano>
> http://mc68k.blogspot.com/2012_10_01_archive.html <http://mc68k.blogspot.com/2012_10_01_archive.html>
> 
> There are even a couple of fairly advanced 68030 design floating around:
> 
> https://www.retrobrewcomputers.org/doku.php?id=boards:sbc:gryphon_68030:start <https://www.retrobrewcomputers.org/doku.php?id=boards:sbc:gryphon_68030:start>
> https://www.retrobrewcomputers.org/doku.php?id=boards:ecb:kiss-68030:start <https://www.retrobrewcomputers.org/doku.php?id=boards:ecb:kiss-68030:start>
> 
> (I have a soft spot for 68k.)
> 
>         - Dan C.
> 
> Well, Rob Pike designed one: http://doc.cat-v.org/bell_labs/blit/ <http://doc.cat-v.org/bell_labs/blit/>
> 
> I guess the original hacker scene for the 68K was around Hal Hardenberg’s newsletter: https://en.wikipedia.org/wiki/DTACK_Grounded <https://en.wikipedia.org/wiki/DTACK_Grounded>
> 
> The ready-made 68K SBC’s only arrived 1984-1985:
> 
> https://en.wikipedia.org/wiki/Sinclair_QL <https://en.wikipedia.org/wiki/Sinclair_QL> (I think Linus Torvalds owned one)
> https://en.wikipedia.org/wiki/Atari_ST <https://en.wikipedia.org/wiki/Atari_ST>
> https://en.wikipedia.org/wiki/Macintosh_128K <https://en.wikipedia.org/wiki/Macintosh_128K>
> https://en.wikipedia.org/wiki/Amiga_1000 <https://en.wikipedia.org/wiki/Amiga_1000>
> 
> All these machines are rather similar at the hardware level - 68K processor, RAM shared between CPU and display. Only the Amiga had a (simple) hardware GPU.
> 
> What set the SUN-1 apart was its MMU, which none of the above have.
> 
> What influenced the timing was probably that Motorola made the 68K more affordable by the mid-80’s.
> 
> Paul
>