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Macintosh SE/30 logicboard recreation (thread revival)

daanvdl

Well-known member
Neat!

So, if I'm not mistaken, this is the only major piece that prevents this new SE/30 board from being fully open source and reproducable, yes?

c
Unfortunately, there are a number of other chips that are not produced new. The GLUE is just “one of them”.
All "custom" ICs on the BOM are difficult or impossible to find.
 

pgreenland

Well-known member
@Bolle I'm sure I've mentioned before but amazing work!

I've finally run out of patience with my battery damaged logic board and going to order some shiny new ones :)

Couple of PCB Assembly questions I don't want to screw up:

Edge Rails/Fiducials: Added by JLCPCB?

C33 C34 C44 C67 C73 - They're down as 33pF but the part listed in the BOM is 10pF....I take it that it should be 33pF?

L1....L22 - Appear to be unavailable, the closet substitute I could find was C710526 (3.5A 1 20mΩ 180Ω@100MHz ±25% 1806), slightly lower current and slightly higher resistance at 100Mhz - would this be a suitable replacement?

Any advice appreciated....looking forward to getting the 4 dead SE/30's in my spare room back on their feet.
 

croissantking

Well-known member
@Bolle I'm sure I've mentioned before but amazing work!

I've finally run out of patience with my battery damaged logic board and going to order some shiny new ones :)

Couple of PCB Assembly questions I don't want to screw up:

Edge Rails/Fiducials: Added by JLCPCB?

C33 C34 C44 C67 C73 - They're down as 33pF but the part listed in the BOM is 10pF....I take it that it should be 33pF?

L1....L22 - Appear to be unavailable, the closet substitute I could find was C710526 (3.5A 1 20mΩ 180Ω@100MHz ±25% 1806), slightly lower current and slightly higher resistance at 100Mhz - would this be a suitable replacement?

Any advice appreciated....looking forward to getting the 4 dead SE/30's in my spare room back on their feet.
I got these inductors for L1-L22:

 

croissantking

Well-known member
An update on my build. I've been stuck on the death chimes and simasimac pattern for weeks, but tonight I've had a breakthrough. I swapped out the GLUE chip from another donor board and I now get a boot chime and a grey screen with movable cursor. But the flashing disk icon never appears.

I remember testing the donor board that the components came from and it had exactly this issue.

I know that this particular symptom is indicative of a possible problem with the SCSI chip, but I've installed a new chip that I bought off eBay. Do the SCSI header and external ports need to be in place, I have not fitted them yet?

What else could be wrong?

IMG_8913.JPG
 

daanvdl

Well-known member
Ports doesn’t need to be connected for booting.
It looks like the code is waiting for “someone” to be ready.
Can be a connection or a faulty chip. Check for bad solder connections around GLUE and the PLCC’s. Is the ADB chip polarized the right way? Is the RTC known working?
 

croissantking

Well-known member
Ports doesn’t need to be connected for booting.
It looks like the code is waiting for “someone” to be ready.
Can be a connection or a faulty chip. Check for bad solder connections around GLUE and the PLCC’s. Is the ADB chip polarized the right way? Is the RTC known working?
I’m thinking faulty chip. Good call on the RTC, I’ll socket it and try another one.
 

robin-fo

Well-known member
Grüezi, I would be interested in your mouser parts list, I´ll order some boards too and need some parts. Thank you
I'm sorry to have kept you waiting, but I couldn't find time to re-check everything. I attached a csv (renamed to .txt to be able to upload it here) containing almost all parts I ordered for the SE/30. The ferrites are missing (see earlier in this thread for replacements), as well as all bottom side parts because my boards were pre-populated by JLC. Also check quantities, some components are enough for two boards.
No guarantee for anything :)
 

Attachments

  • SE-30 Warenkorb_Jan05_1252.txt
    6.4 KB · Views: 23

croissantking

Well-known member
So after feeling a lot of excitement at getting to the grey screen I’m now totally stumped once again. I’ve run a test using AppleCAT from another machine connected by serial link, and it passes all tests (ROM, RAM, address bus, data bus, PRAM, VIA, clock and FPU) until it gets to the sound test, and fails (even though sound seems to work just fine). I’ve subsequently replaced the ASC and Sony chips but there’s been no change. I’ve also replaced the SWIM, SCSI and RTC chips and even the big crystal oscillator for good measure. I’m literally out of ideas now :(

I have two donor boards and all of these components came from board #1 (bar all the ones I’ve now started swapping out from board #2). Board #1 had exactly the same problem of being stuck at the grey screen with mouse pointer but sans floppy icon, so this tells me that I’ve transferred whatever bad voodoo it is across to the new build. Board #2 successfully booted up off a hard drive so I’m confident that the parts I’m using from it are good.

Where do I go from here?
 

croissantking

Well-known member
If it helps with diagnosis, it starts booting (but doesn’t finish) with the RTC chip removed from the new socket I put in last night.

I’ve tried two different chips and I’m pretty sure the second one from board #2 works. (Although I suppose there is a possibility I’m wrong - but it does pass the clock tests in Apple CAT)
228E6FCC-4C35-4288-8973-05C412F0B2BC.jpeg
 

daanvdl

Well-known member
Maybe these are helpfull for the audio circuit troubleshooting?8E62D6B7-2D08-4CD9-B720-63A90FFFD816.gif
 

Attachments

  • FD6C6588-051E-4942-9D2C-B16A6EDBFB7E.png
    FD6C6588-051E-4942-9D2C-B16A6EDBFB7E.png
    28.4 KB · Views: 23

croissantking

Well-known member
Here we are. Everything seems to be working just fine - I can click the mouse, boot off a floppy or HD and it passes the audio test now.

I am thinking it was the VIA that was the issue - but I replaced the choke at the same time so it's hard to be sure. I'll know pretty soon as I start to put together my second build.

IMG_9034.JPG
 
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