SE/30 not detecting BlueSCSI (internal or external)

wottle

Tinkerer
Oct 30, 2021
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Fort Mill, SC
I picked up a SE/30 that had some pretty significant capacitor leak damage. I had a transistor at Q3 fall off the board from corrosion. I didn't initially see it, but I had pin rot on UE8 that lead to a jail bar pattern on the screen. I replaced Q3, and installed a brand new UE8, and the machine now boots with a good screen with no bars.

The next problem is that I can only boot from floppy (I used Floppy EMU and it boots into 6.0.8 fine) . When I try to use BlueSCSI to boot, I only get a solid red light on the BlueSCSI and the machine gives me a disk with a question mark. This is the same whether I use an external BlueSCSI or the internal connector with an internal BlueSCSI.

What should I try for troubleshooting. I'm not great at FloppyEMU and loading software (I typically use the BlueSCSI for that). Are there SCSI utilities I can use to see if the SCSI port is functioning. Are there chips on the board for doing SCSI I can inspect for pin rot? Traces I can inspect more closely?
 

eric

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Sep 2, 2021
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Start here in the troubleshooting guide - after you've gone through that let us know if you're still having issues or resolved it.

 

wottle

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Oct 30, 2021
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Sorry, I should have made it clear that I can use these BlueSCSIs with their SD cards in my other SE/30 and they work properly. I wasn't trying to imply the BlueSCSI was the issue, just wondering if the solid red led on the BlueSCSI might help track down why the SCSI ports on the SE/30 aren't detecting the devices plugged into them.
 

eric

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Doh! I know there is a fuse near the scsi chip that can fail regularly but you wouldn't have term power if thats the case. May be worth inspecting the passives near the SCSI chip. I have heard people replacing the scsi chip too as they've had a failed one, they are obtainable.

Another thing I would do is check the voltage of the 5v line - this one could have a low 5v and cause poor termination which would result in what you described too.
 

wottle

Tinkerer
Oct 30, 2021
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Fort Mill, SC
That was useful. I checked the 5v pin on the bluepill, assuming that would carry through the voltage from the SCSI 5v line. It was less than 3v. I'll check out the pins from the analog board to see if the voltage is bad there, or if there is a problem on the analog board getting the power to the SCSI ports. It's probably worth noting that I have not recapped the analog board (I was trying to fix the jail bar pattern and logic board damage first. I'll probably recap it just to get all new caps on the logic board. In the meantime, I'll connect the logic board to one of my other working compact Macs with a recapped analog board and see if the SCSI port works. with a better power signal.
 
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wottle

Tinkerer
Oct 30, 2021
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So it seems to be a problem with the logic board, as I plugged the board into my other SE/30 (known working analog board) and got the same behavior. I'll take a closer look around the SCSI chip for anything that looks out of place.

I may simply save this board and use it with the SE/30 reloaded group buy that's been discussed here.
 
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wottle

Tinkerer
Oct 30, 2021
476
236
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Fort Mill, SC
So it seems to be a problem with the logic board, as I plugged the board into my other SE/30 (known working analog board) and got the same behavior. I'll take a closer look around the SCSI chip for anything that looks out of place.

I may simply save this board and use it with the SE/30 reloaded group buy that's been discussed here.
Just to follow up on this - there was significant damage around the SCSI chip. I tried to remove and replace, attempting to repair the pads that fell off the board during removal, then installing a new SCSI chip . but I have now been left with a machine that has horizontal black bars across the screen :(. I guess I'm waiting on that SE/30 reloaded group buy!