Any chance of using manual inject floppies on LC II/P475?

[Addicted]

Hello all. I have an inventory mismatch going on here. I've accumulated a few working manual inject SuperDrive floppy drives, Sony and Mitsu. I also have a few LC-type systems that would complete their restorations if they finally had floppies. Trial and error tells me that the LC I and LC II differ in how they handle auto-inject versus manual-inject floppies. I presume the P475/LC III can't use manual injectors, but haven't cleared my workbench to try the pairings out for the LC475 and find out.

In a word, the LC I seems fine with manual injectors. Inserting a disk during runtime causes the disk to be accessed. The LC II does not detect insertion on the manual injectors, and nothing happens. Both systems can boot from a disk in either type of drive if the disk is inserted before power-on, so I conclude it's about insertion detection.

I'm seeking existing posts here that can educate me about this. Auto-injuect drives are gettingrare and if there's a mod I can make to get the floppies all working in the systems, I can finish out a few good systems.

One can see just from the logic boards that the floppy support differs across the systems. The LC I has a perfect twin for a second floppy connector on the logic board; the others have only 16 pins on the second connector, which is unpopulated. So I'm really only concerned with the primary floppy on all of these systems.

(I'm not 100% certain the mechanics work out yet. The manual-injectors will have the manual-inject levers in the wrong place, that is clear; but the drives also have bezels (dust doors) which may not clear the inside of the chassis face. One thing at a time.)

 

[ymk]

P475 came in both auto and manual.

 

[nathall]

In my experience, the logic boards can’t tell the difference. It’s only ever the bezels that cause issues. I ran my IIfx for years with one auto and one manual. That’s odd the LCII doesn’t do anything with a manual. I don’t know why that would be. The LCIII shipped in both configurations.

 

[volvo242gt]

My old Centris 650 had a manual-inject drive installed in it when I got it. Worked, but you had to use another floppy to insert the disk all the way. I'd expect the LC series machines with the older case lid to be the same. Since the LCIII/III+, Performa 460, 466, and 467, all have the option of the later LC 475 style case lid, you can always swap one of those on, and it'll work. A dual-floppy LC will probably lose the ability to access the second drive, of course, since there's only one floppy disk slot on the later lid. You'd have to custom modify it to work.

With respect to the LCII board not recognizing the later drive, I wonder if there's some voltage issue that's causing it to ignore the floppy drive once it's booted up.

 

[nathall]

My old Centris 650 had a manual-inject drive installed in it when I got it. Worked, but you had to use another floppy to insert the disk all the way.

Yeah, that’s the way it was on my IIfx.

 

[alectrona6400]

I'm actually quite glad to hear the manual drives will work fine in almost all auto macs, those drives are getting harder to find in working condition. But yes... there are definitely some caveats. I personally like the feel and sound of the auto drives, brings me back to when I got my first 68k mac in 2017, a Macintosh Classic.

 

[Addicted]

Excellent to have some replies, thanks all for reading.

I was testing these in rapid-fire, and as such had the lids (chassis covers) off. And also as a result, I didn't take written notes. I'll repeat this matrix again sometime, possibly within the week, and take better notes. But I can say for certai that this wasn't an issue with inserting due to the lack of the finger-valley on the face of the chassis.

I'm also hoping to have the time/energy to look very closely at how the floppies detect a disk insertion. Perhaps this is all just a matter of dust bunnies obstructing an LED/photodiode pair, or blocking an open-air leaf switch.