68kMLA Classic Interface

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Mock Floppy Drive (Floppy Emu case mod experiment)
Posted by: AEChadwick on 2025-05-22 15:01:21 I have been working on a Mock Floppy Drive. My goal is a drop-in unit with a Floppy Emu at its heart, albeit with the screen and controls moved to a fake floppy disk that pops in and out like a real disk. There is no need for this device, it solves no problem, and might be completely wrong-headed—i just like having an impossible project. So far, i have made a little intercept board using an ATMega328 and a couple 20-pin connectors. When a disk image is ejected, the board catches the eject signal on its way to the Floppy Emu; when it catches an eject signal, it turns a little servo—out ¼-turn, pause, then back to origin... like a little pressing-finger. This will serve to push a button or flip a latch to pop the mock-floppy out. I devised a micro-latch mechanism, but it is not sufficient... I need to figure out Auto-INJECT. It's just not reliable to push-to-latch the disk all the way in, and it's not magic. The grabbing motion of Auto-Inject would be perfect. Has anyone ever encountered a reverse-engineering of the Auto-Inject mechanism? I cannot find any example anywhere online. I even tried explaining it to a couple engineers, begging for a working model (or a workaround). (They said "that sounds cool!" and went on with their day.) I will post updates. They will be infrequent. This is a fool's errand. Please share ideas, i appreciate any help.
Posted by: AEChadwick on 2025-05-22 15:08:01 the board is dead simple; i asked a friend to throw the code together, “sure, that sounds easy.”
Posted by: finkmac on 2025-05-22 16:24:57 oh my god that's awesome. i've thought about something like that before, really cool to see someone actually making one.
Posted by: jmacz on 2025-05-22 21:19:39 Did you consider just reusing the floppy mechanism (Eject motor, brackets, etc)? You could repurpose the disk switch to detect the inserted case. You would just have to replace the actual floppy with something holding the display/etc.
Posted by: AEChadwick on 2025-05-23 07:11:45 Did you consider just reusing the floppy mechanism (Eject motor, brackets, etc)? You could repurpose the disk switch to detect the inserted case. You would just have to replace the actual floppy with something holding the display/etc. i had one non-working drive that i decided to dismantle: i couldn't figure out how to just get the mechanism separate. Worth another try, but drives are limited. the bigger problem is: the servo just doesn't have enough torque to push the existing metal cage around. It can flip a wee switch, but not push that eject button—you only have 5V @ ~300ma, and you have to share it: to much draw trips the power and resets the Floppy Emu. A custom mechanism would be the most fun & provide the most control. Also, it's more difficult & fraught, so: that's The Chadwick Way.
Posted by: jmacz on 2025-05-23 07:21:12 I see. I was thinking you could reuse the existing eject motor as it seems pretty strong, then you also wouldn’t have to push for eject as you could just trigger the motor in the same way the drive does now.
Posted by: AEChadwick on 2025-05-23 10:17:03 I see. I was thinking you could reuse the existing eject motor as it seems pretty strong, i will play with that, the OMRON R2DG-38 is really just a fat little servo itself... (but i'd still love to understand the Auto-Inject mechanism...)
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