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LC II dual floppy ports possible with soldered connector?

Posted by: zezba9000 on 2021-12-21 22:34:04 Macintosh LC has two floppy connectors on its motherboard. LC II only has one BUT has what looks like a spot for it. If I solder a connector here will it work?

Posted by: max1zzz on 2021-12-22 09:58:40 That port isn't a floppy connector on the LCII, it only has 16 pins and connects to the V8 not the SWIM I have no idea what it actually is, so if anyone has any info on that I would be very interested!

Posted by: Fizzbinn on 2021-12-22 12:31:45 Isn't the V8 video? WILD guess: Internal video connector for a never released all-in-one design?

Posted by: zezba9000 on 2021-12-22 12:50:57 16 pins and connects I see guess I didn't take close enough look as it was in the same spot.

Posted by: cheesestraws on 2021-12-22 15:12:21 Per the Bomarc schematics, J18 picks up two unlabelled glue signals, three address lines, a clock and a lot of grounds. I have no idea what it's for: looks like it might as well be labelled "miscellaneous".

Posted by: Addicted on 2022-09-17 10:46:37 I was pondering this question just last week. Firstly, I think for a second floppy connector, you need only clone the existing connector but replace the new connector's enable line with the other enable line. You'd have to (carefully) solder a wire directly to the SWIM to get that signal, as it's a no-connect on the board. I was wondering if that's all it takes - if the OS/ROMs will poll that drive, if one is connected. As far as J-18 goes.. no idea, but I will speculate. I was thinking it might be a diagnostic, development, or debug port.. not intended for product use. Allows attachment of logic that can drive the GLU to dump its state, do some sort of tracing, etc. No idea. I need to read more about what GLU does and what it is.

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