[rescue] sun 3/60 update

[Dave McGuire]

On 5/21/25 12:51, Dan Moisa via rescue wrote:
> RE: boards and making it available - absolutely. I have 4 additional 
> boards from the initial run (min of 5 order) and I won't be needing all 
> of them. The first run needs 2 trace corrections on the board itself 
> (intermediate-level soldering) so for those interested I can patch the 
> board and send it out/etc.
> 
> I'll post everything on Github - I have an almost-final version on there 
> right now but it's not organized well, etc. I made the project with 
> KiCAD, and I'll put all the schematics, etc. as well as consolidate the 
> pal images, put up some build instructions (I spent a lot of time 
> building incrementally and testing, and it was a lot of help).

   Great!  Thank you for sharing your design.

> Right now it's a 4-layer board with signals on the top and bottom, which 
> was the right call. I wanted to make sure I can fix small errors if I 
> find them, and I did have 2 places where I had to change the connections 
> to make it work. It was a pain to route it, I managed to do most of it 
> with the autorouter in KiCAD but it took over 2 weeks of fiddling with 
> it and the actual routing run took over 12 hours.

   I was thinking of taking a whack at SMTizing it, but would only do so 
with your blessing.

> Dave - I'll probably wire another one up, test it and ship it to you. 
> I'm doing this purely for preservation and admiration for what the SUN 
> folks did back in the day - having a computer from '87 with software 
> from '92 able to get on the Internet today is quite something.

   I appreciate that very much, but I don't need you to go to all that 
trouble; a bare board and JEDEC files will do.  It's likely that I have 
most or all of the components here anyway, save for possibly the 68020 
socket.

> The biggest issue was actually burning one of the PALs - I ended up 
> wasting quite a bit of money on programmers to find one that actually 
> works. Whoever wants one of those just tell me and I can ship you a set 
> of burned PALs/GALs.

   I can burn the PALs. (meaning for myself, but also for anyone who 
needs them)

> RE: vintage or not, I'm somewhere in between. The first version I wanted 
> to have it as close to the original as possible so I can easily test - I 
> had no confidence that the schematics are complete and free of errors, 
> and I did actually find a few but nothing major. Having it be similar to 
> the original helped a lot because I could do knockout testing - remove 
> components and see how it behaves, and test that I get the same 
> behavior. It was also huge to be able to test the burned PALs, I had a 
> few bugs in that as well. I also tried to keep more or less the same 
> layout - compressing a bit of course.

   That sounds like the right approach.

> I already have a standard molex power connector on it (not soldered 
> right now because of the amount of incremental building and testing I 
> did on it). It also only needs 5V and the 12V are only for Ethernet. It 
> pulls about 3.5A (and negligible on 12v) while running a full load.

   That's not bad at all.

   I'm sure you'll be inundated with suggestions (it appears to have 
already begun) but I recommend adding a screw-terminal power connector, 
perhaps Phoenix MKDS or similar (KiCad has footprints for these), in 
parallel with the Molex.

   I would also love to see a 68881/68882 socket. :)

              -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA