68kMLA Classic Interface

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SE/30 with non-working yet known-good floppy
Posted by: broderbund on 2026-01-31 18:33:34
Hey folks! I have been restoring my SE/30 and have gotten just about everything working post-recapping except the internal floppy drive. I have a known-good drive (tested with an SE board swapped into the SE/30) which the SE/30 is incapable of reading, writing or formatting. It powers up, the drive spins, and it can eject, but that's it. The drive head doesn't move forward or back. I've already replaced the SWIM chip with one from a IIci donor, as well as the Bourns filter at RP11. Any ideas for my next troubleshooting steps?

thanks!
Posted by: Nixontheknight on 2026-01-31 18:46:48
try checking continuity between the SWIM and the floppy connector. I know SE/30 schematics exist somewhere, so that should help you should any traces not have continuity
Posted by: broderbund on 2026-02-01 05:53:22
I should mention that I've checked continuity between the SWIM and: the floppy connector, the IC at UH7, and the 68030. Though it's worth doing again!
Posted by: broderbund on 2026-02-02 18:04:52
And guess what. I replaced / reseated the SWIM a couple more times and things are now working! That surface-mount soldering is always a beast.
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