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Macintosh SE/30 logicboard recreation (thread revival)
Posted by: CC_333 on 2022-12-28 13:27:21 I already sent one out to get it imaged when the logicboard project first started: https://siliconpr0n.org/map/apple/344s0602-a/mz/ So technically it’s just about tracing out the connections and map out the gate layout accordingly. 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
Posted by: daanvdl on 2023-01-02 03:32:23 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.
Posted by: joshc on 2023-01-02 04:01:04 The RTC and ASC are the other main ones.
Posted by: pgreenland on 2023-01-02 05:40:53 @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.
Posted by: croissantking on 2023-01-03 04:18:04 @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: https://www.mouser.co.uk/ProductDetail/Taiyo-Yuden/FBMJ4516HS111-T?qs=I6KAKw0tg2y40ZosKwS0Og%3D%3D&countryCode=GB&currencyCode=GBP
Posted by: daanvdl on 2023-01-03 12:42:14 For those who are interested; I measured the ferrite beads located at L22,L20,L19,L18,L17,L16,L15,L14,L13,L12,L11,L10,L9,L8 with my VNA. Hereby a sweep resistance output from 1Mhz to 500Mhz. M1 is at 100Mhz 92Ohm with a low Q factor. View attachment 43510 Taiyo Yuden FBMJ4516HS111-T is matching this curve. I used these on 4 boards without any problem.
Posted by: croissantking on 2023-01-05 20:03:22 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?
Posted by: daanvdl on 2023-01-06 00:55:01 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?
Posted by: croissantking on 2023-01-06 01:57:19 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.
Posted by: robin-fo on 2023-01-09 08:57:49 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 🙂
Posted by: croissantking on 2023-01-11 03:19:15 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?
Posted by: croissantking on 2023-01-11 07:27:17 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)
Posted by: daanvdl on 2023-01-12 13:19:42 Maybe these are helpfull for the audio circuit troubleshooting?
Posted by: croissantking on 2023-01-12 17:17:49 Maybe these are helpfull for the audio circuit troubleshooting?View attachment 51115 Thanks, yes. But I can’t believe it’s the audio circuit that’s bad, since I swapped out the components shown above.
Posted by: daanvdl on 2023-01-13 10:19:13 Any change to swap the GLUE between the known working and this board?
Posted by: croissantking on 2023-01-13 10:20:16 Any change to swap the GLUE between the known working and this board? I’m already on my second Glue chip - the other one was completely screwed.
Posted by: croissantking on 2023-01-16 01:59:34 Got it fully working now. Either a bad VIA at UK11, or a bad common mode choke at L1.
Posted by: croissantking on 2023-01-16 02:45:19 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.
Posted by: rollmastr on 2023-01-16 02:57:00 Awesome, congrats!
Posted by: Cam on 2023-01-16 06:08:09 Fantastic!
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