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| SE/30 not booting from BlueSCSI | ||
| Posted by: jasper7474 on 2026-09-05 18:10:58 Hello everyone, I bought my first 68k Macintosh recently, an SE/30, and found that it has had its 1.44 MB floppy SuperDrive replaced with a lame 800K one, and also found that it was missing its hard drive, so I bought a BlueSCSI. When it finally came in, I plugged it in, put an SD card with System 6.0.8 in, and turned it on to only get the ? floppy icon after about 15 seconds after power on. I've done a lot of troubleshooting with the BlueSCSI itself (firmware updated, filenames correct, jumpers properly set, bluescsi.ini is pretty minimal) and feel I can safely rule it out. The logs from the latest run are attached. I've read a lot about the SCSI chip being overly sensitive and needing some modifications or replacement, so I've done resistance tests on most of the important control and data pins from the SCSI chip to the 50 pin connector, and I've verified that my SCSI cable is good. There is a wire that someone patched from the READY pin (which also has had its leg cut off) on the SCSI chip to a pin on one of the VIAs. I concluded that I should at least try the 4.7k resistor across pin 26 and pin 48 on the connector pins on my BlueSCSI, but that unfortunately did not work. Any help would be appreciated! | ||
| Posted by: finkmac on 2026-09-05 18:22:09 1. has the mac been recapped 2. which bluescsi is this? the 1.x one is a defective design... don't use that one. other Zulu-Compatible SCSI Emulators (like the BlueSCSI 2) are safe. 3. sounds like someone has been messing around in there. got pictures of these patches you're talking about? | ||
| Posted by: jasper7474 on 2026-09-05 18:41:58 1. Logic board has been recapped by the previous owner (he owns another SE/30, so I guess he knew what he was doing? maybe?). Looks good enough to me. 2. BlueSCSI v2, bought it brand new from Joe's Computer Museum. 3. Yeah, definitely a few strange things. Unrelated, but the 800K floppy drive, which isn't even the kind of floppy drive it came with new, didn't have a cable connected to the logic board, so I ordered one before I realized it wasn't the SuperDrive. Here's a really crappy photo of the wire (this is the only suspicious thing to me). To reiterate/clarify, the leg that the wire is connected to on the SCSI chip has been cut and is not making contact with the board. The wire is its only connection. However, the wire seems to be pretty well soldered on, it's not a loose connection.  | ||
| Posted by: dragorn on 2026-09-05 21:06:56 Q3 also looks to be missing? | ||
| Posted by: dragorn on 2026-09-05 21:18:01 Looking at the schematics, Q3 looks to be related to ADB, and that bodge wire looks like one of the data lines between the scsi and the via chips. q3 probably wouldn't prevent scsi from working, but wackiness on the scsi data pins sure could. | ||
| Posted by: jmacz on 2026-09-05 22:12:17 That bodge wire is connecting a data line (d24) between the scsi chip and via2, probably cuz it got severed. Double check that that bodge has continuity with other chips accessing it d24. But if you are missing q3, and looking at that radial capacitor used for c11, you may have other issues on that board. | ||
| Posted by: finkmac on 2026-09-06 05:02:09 agree with @jmacz . unfortunately recapped non-working boards are annoying as you have to deal with someone else's subpar work. you're getting far enough in booting that most stuff is working. for now, I'd tone out every SCSI connection on the board. | ||
| Posted by: killvore on 2026-09-06 05:26:36 Watching this thread since I'm in a similar situation - I have an SE/30 that boots fine from floppy but can't find a known good SCSI hard drive (recapped by me, so I am sure i messed something up) | ||
| Posted by: jmacz on 2026-09-06 08:01:36 One of my prior ones had a broken trace near a via next to the three caps near the main logic board connector. Another required the scsi chip to be replaced. I just got two more so will see what happens to these. | ||
| Posted by: jasper7474 on 2026-09-06 13:16:32 Thank you all for your advice. Q3 is in fact missing for some reason, I've never noticed that. I believe this is the correct replacement part for it? I don't see anything wrong with C11, I checked this schematic and it has the correct properties. I toned out all the connections that D24 makes and they're all good, so the bodge wire is doing its job. I've also just toned out the rest of the SCSI chip connections and all the traces seem to be good. In my initial post I said I put a 4.7k resistor in, but turns out it was a 10k, if that makes a difference. | ||
| Posted by: jasper7474 on 2026-09-06 17:20:05 Just remembered that my dad did take a look at the BlueSCSI itself before I was troubleshooting anything on the logic board, and he was a bit skeptical of the soldering job done on the Pico 2W to the BlueSCSI board, so I reflowed it, eliminating that possibility. | ||
| Posted by: saybur on 2026-09-07 06:12:48 Congrats on getting your first retro Mac and sorry it's been a pain for you. Try temporarily enabling debug mode on the BlueSCSI. That will log a bunch of SCSI traffic elements that might help narrow down the problem. If there's a bunch of BUS_BUSY/BUS_FREE elements you'll at least know the SCSI chip is running and trying to find stuff on the bus (or not). If you have any other working older systems, even like old PCs that could fit a SCSI card, it may be worth trying to verify the BlueSCSI works there before tackling the SE/30. PCI SCSI cards are generally reliable and can still be had for relative peanuts on eBay. | ||
| Posted by: jasper7474 on 2026-09-07 06:26:56 @saybur Yes, I've had debug mode enabled, and it would appear that the BlueSCSI is working. Unfortunately, I don't have another machine to verify its operation, but the BlueSCSI is logging what you mentioned - BUS_BUSY and BUS_FREE, and it seems to be working and is able to select the right SCSI device ID, but the Mac SCSI chip sends back "unknown" command 0xFF and it times out from there (or something like that, that's what ChatGPT told me 😅). Here's a log from it where I left it on long enough that you can see how it repeatedly attempts. | ||
| Posted by: saybur on 2026-09-07 07:18:38 Well that's a weird log file. Selection is fine and getting six bytes of command data is (AFAIK) the normal first step during Mac startup, but the bytes are junk and that read timeout is not right either. Maybe the bus phase isn't being detected right by the Mac? May want to check continuity between the SCSI port MSG, C/D, and I/O pins and the SCSI IC. I'm no expert at reading BlueSCSI log files so you may also want to consider asking in their Discord, it's fairly active. | ||
| Posted by: jasper7474 on 2026-09-07 07:46:40 I have checked continuity for all the connections that the SCSI chip makes, and it seems to be fine, so I'm beginning to lean toward getting a replacement chip. I did find it on Utsource, which is a bit sketchy-looking. Any suggestions on finding a replacement? | ||
| Posted by: Fred1212 on 2026-09-07 21:21:59 You really need someone nearby to test with another Mac to eliminate a faulty BlueSCSI maybe | ||
| Posted by: jasper7474 on 2026-09-08 06:05:52 Unfortunately I do not know anyone else with a retro Mac. I just ordered a replacement SCSI chip, so fingers crossed that's the solution. If it's not, I'll quadruple-check the BlueSCSI and make absolute certain it is fully functional. Based on my troubleshooting thus far, the BlueSCSI is the last thing I suspect to be the problem. | ||
Posted by: ESM-NL on 2026-09-14 02:31:59I concluded that I should at least try the 4.7k resistor across pin 26 and pin 48 on the connector pins on my BlueSCSI, but that unfortunately did not work. Any help would be appreciated!Here an example of the BlueSCSI log.txt from my SE/30:
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| Posted by: kris92 on 2026-09-20 23:14:03 Hello, I had a simular problem with a new macintosh SE reloaded board. The problem was the system disk image file I was trying to use. Did you try another distinct images ? | ||
| Posted by: jasper7474 on 2026-09-21 18:57:35 I did try a few different images. All of them were valid, bootable images to my knowledge. I was able to look at a dump of it and could see the proper header bytes, and also the Linux file command said it was a Macintosh bootable image. I believe the issue is just a defective SCSI chip, and after about a week and a half wait, I just got the replacement in from China. I'll be letting y'all know if that was the solution once I can get access to a hot air station. | ||
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