Is the floppy drive inside the UltraBay FD interchangeable?

[danikayser84]

Like with the CD/DVD drives which use a standard IDE laptop optical drive, are the floppy drives inside the FD modules also interchangeable between like the 75x/76x, 600, T2x/T3x/A3x generations? They seem to use the same connector between the three (inside the caddy, not the UltraBay connector itself), but are they interchangeable? (are PC laptop floppy drives standardized to begin with?)

Recently I had the floppy drive in my PowerBook G3 Wallstreet die, so I found that I could swap in a drive from another PowerBook (from 1xx to 1400 era) and it will fit and work inside the module, and I thought it would be interesting to try putting a spare 2.88MB drive into a T2x/T3x/A3x UltraBay floppy drive

[RealBlackStuff]

I know that T2x and T3x can use the same floppy drives. (I have a few spares, if needed).
Never had an A3x or older machine to try them on.

[automobus]

are they interchangeable? (are PC laptop floppy drives standardized to begin with?)

Pretty much, yes. They are different to Apple's drives. Most-all IBM-PC-compatible floppy drives are usually interchangeable; this truth follows for slimline formfactor. Here is a pinout, and here is a datasheet (TEAC FD-05HF-8830) of a typical representative 12.7mm-thick "slimline" or "micro" floppy drive. Its connector is 26-pin, 1mm pitch, 0.3mm thickness flexi-ribbon.

[danikayser84]

Update: I tried the bare 755/760 2.88MB drive in a UltraBay 2000 caddy (T23 and A31) but it only was seen by both Windows 98SE and Windows XP as a 1.44MB drive so there must be a BIOS limitation Also tried it on a 560Z (in a 600X UltraBay caddy and external bay) but still only sees it as a 1.44MB under Windows 95... so it seems like the latest machines that can use a 2.88MB floppy are the 760XD/XL and 765D/L

It was well worth experimenting though

[thinkpadcollection]

Floppy drives themselves (not the controllers that drives them), heads are "driven" analog signals pulses.

Cheers, thinkpadcollection

[automobus]

I'd say it is, well worth experimenting, for fun. I have never seen 2880 Kio (ED) floppy stuff. I have merely read of them. It might be possible for O.S. to override/bypass BIOS/CMOS floppy drive description information. Then, you might get your ED drive to work in newer ThinkPads.

For Linux, it ought to be possible to specify floppy drive description at boot prompt. (fdutils documentation) (Another document to read, which is much shorter than that fdutils, is kernel Documentation text floppy.txt.) One could try 'floppy=0,6,cmos'.

For DOS, 'DRIVPARM can override the type of an existing drive'. 'The DRIVPARM command modifies the parameters of an existing physical drive.' One could try 'DRIVPARM=/D:0 /F:9'.

I asked Bingle, but did not get any information for Microsoft Windows. If I were in your shoes, then I would try asking on MSFN.

[thinkpadcollection]

The limitation is floppy controller chipset in part of motherboard components determines 2.88MB or 1.44MB support. Vast majority of the computers out there are 1.44MB/720K sectors format. To have 2.88MB to work different FD chipset needs to be used which is not possible, round up a computer with one and use it.

Cheers, thinkpadcollection