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That Mascintosh disk is like one of those rare misprint stamps with an upside-down airplane. I love it.

Applesauce and the Floppy Emu also both support MOOF format, which is a bit-level disk image of a 3.5 inch 400K or 800K floppy. This is a new format designed by Applesauce's creator, and that's only been around for a couple of years. At the bit level it doesn't matter if the disk is Macintosh or...

Thanks! I don't think that post was there yet when I looked yesterday - it explains the feature nicely. Very cool, thanks for doing this.

After reading the summary and the GitHub, I'm still a little unclear exactly what this does or how it's intended to be used. I think this is for mounting the SD card on a modern computer remotely, instead of putting the SD card into a card reader attached to the modern computer. How does it...

You could reverse-engineer the entire schematic from those photos, maybe that would give more clues. Of the eight (?) I/O signals, I count four connected to the low four output bits on the '259 latch, one connected to an output from the '04 inverter, and three connected to inputs on the '153...

There's also L1 and L3 to the right of the connector, and L8 and L9 at the far left, and (in smaller packages) L5 and L6 at near left. That's a lot of inductors! I would guess they're there to help filter out high frequency noise from power supply rails and other DC signals. My prediction would...

I count six power pins and eight I/O pins, leaving two pins unused unless I missed something. The presence of a shift register is a strong clue this is some type of serial I/O card. Since it was installed in slot 3, I'm going to guess it might be an interface card for a PC-style serial mouse...

There's no ROM, so the software needed for this card would have to come from somewhere else. The chips are a couple of 8-bit registers, a shift register, a mux, an 8-bit latch, and OR and NAND and NOT gates. I think slot 3 was often used for 80 column cards or mouse cards, but I don't recognize...

Yes, try disassembling it far enough that you can test the switch contacts with a multimeter while you press and release the switch button. The button might be sticky or dirty, preventing it from popping up all the way when there's no disk. Or there might be junk inside the switch that's...

DiskCopy4.2 can make accurate images of Lisa disks on a Mac. You just need something that will preserve the tag bytes in each sector, which it does. How about firing up that IIgs sales demo?

The voltage regulator surgery was successful! My Quicksilver now goes to sleep and wakes up normally with the SATA card installed. For anybody reading this in the future, I recommend using the Diodes Incorporated AP7361C-33E voltage regulator, and not the MIC29150 that was suggested earlier...

With component placement:

I'm still not completely clear - you're seeing an "X" floppy disk on the Mac even when no disk is inserted in the floppy drive? I also see a 0.22uF capacitor that's been bodged onto the pins of an IC near the front of the drive. Was that a previous repair?

I think the hardware design is finished. I couldn't fit the whole list of monitor IDs on the back, but I included enough to cover the most common cases.

The best explanation I've seen is that they wanted to start the time base on a leap year for some reason, and 1900 was not a leap year. So 1904 is the furthest back you could go without including 1900 in the range of supported dates, and needing to explicitly encode 1900 as an exception to the...

My first thought was that Apple deliberately chose a time base in the past, so that time values could be used for things like dates of birth and not just for the current time. But choosing 1904 would have made it impossible to encode the DOB of anyone over 80 at the time of the Mac's launch.

It should be the one on the right - the one that's not aligned with the write-protect tab on the disk jacket. If your drive is spinning but you don't see an "X" on the floppy disk icon, then your problem is likely somewhere else.

Does anyone have insight into why Apple chose January 1, 1904 as the time base? Is that a standard? If they'd chosen a time base in the year that Mac development started, around 1980, then we wouldn't be worrying about this problem until 2114.

Nice, I'm glad to hear your setup is working well. I'll mention that K(V)M model to anyone who asks. When the Wombat was first designed, mini USB-B was more common than it is now. I need to update the design with micro USB or USB C instead. Since you've got two Wombats, you could stack them...

...and those 20-ish nanoseconds of delay could be very important, if they're the difference between meeting the setup time requirements for data written to video memory, and not meeting those requirements. Touching /NUBUS with a probe would add extra capacitance like I was babbling about...