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SCSI2SD in SE - new issue
Posted by: LaPorta on 2022-07-31 14:28:46
Hey guys, I have had a SCSI2SD (5.1, I think?) working in my Mac SE for a few years now, with no issues at all. Recently, I have had an odd issue: when I turn on the machine, the HD LED (I have it soldered to the SCSI2SD LED header) stays constantly lit, and I get the classic blinking question mark floppy. If I cycle the machine on and off, the LED is not constantly lit, and it will read it and start up just fine.

Same thing if I flip it on, and then immediately flip it off and on, works fine. What might be causing the SCSI2SD to behave in this manner?
Posted by: just.in.time on 2022-08-04 23:51:28
My first guess would be a power situation. Has your power supply ever been recapped? If not it may have drifted down a little. There’s a way to check the 5v and 12v lines on the external floppy port on the SE. might be starting every so slightly low then coming up high enough after a second on cold boot. If that’s the case, there’s a way to adjust the output voltage on the PSU.
Posted by: LaPorta on 2022-08-05 02:39:27
Intriguing thought. This SE has been fully recapped, and is thoroughly stable in every way. I can check the voltages via the floppy port and see, however.
Posted by: QuillOmega0 on 2022-08-09 15:07:35
Next time you get the question mark, try to boot off a floppy to see if it can detect the scsi bus then. Do you have any external SCSI devices?
Posted by: LaPorta on 2022-08-09 15:18:49
No external SCSI devices. I’ll give the floppy startup a go, thanks.
Posted by: Skate323k137 on 2022-08-10 07:06:04
Try a firmware update/reflash of the SCSI2SD device itself? Also has the SD card itself been ruled out? (I also use a 5.1 in an SE and have for some time).
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