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400K floppies, 800KB & 1.4MB floppy drives

ArmorAlley

Well-known member
I have confused memories about what floppy drives can format what floppies and a quick search has confused me more.
I have a newly recapped 512K which has a newly greased 400K* floppy drive (thanks @Breathing).
I am setting up an SE now and I would like to be able to format & write floppies on the SE for the 512K.
I have a Floppy Emu for the 512K so the floppy won't be in constant use.
I had thought that I needed an 800KB floppy drive to format 400K floppies and that 1.4MB floppy drives couldn't do it.
From the articles that I found online, reading & writing 400K floppies is and isn't supported by 1.4MB floppy drives and under Systems 7.1 and 7.5.5.
The SE will be running System 6.0.8 and System 7.1.
What floppy drive should I put into my SE if I want to format, read & write 400K floppies: 800K or 1.4MB?
Thanks.

* I should really use the terms single-density, double-density and high-density.
 

LaPorta

Well-known member
Fairly simple actually for the hardware:

400k - 400k only.
800k - 400k & 800k
1.4 MB - 400k, 800k, 1.4 MB

Now, System Software is a different issue. At some point, creating and writing to MFS-formatted disks was disabled (I don't know which offhand). You can still create 400k HFS disks, however.

If your SE is just a regular SE and not an SE FDHD/SE SuperDrive model, you cannot use a 1.4 MB drive. it will only function as an 800k drive unless you have upgraded SE ROMs and SWIM chip in place of the IWM chip in the regular SE.
 

olePigeon

Well-known member
I know you can still work with MFS disks in System 7.1 Pro, but it's a bit weird. You can read and ever write to the disks. But then it gets odd after a file is written. It's almost like it's a write-once disk. You can't modify the disk contents. If you want to make any changes, you have to erase the disk and drag the files over again.
 

ArmorAlley

Well-known member
Fairly simple actually for the hardware:

400k - 400k only.
800k - 400k & 800k
1.4 MB - 400k, 800k, 1.4 MB

Now, System Software is a different issue. At some point, creating and writing to MFS-formatted disks was disabled (I don't know which offhand). You can still create 400k HFS disks, however.

If your SE is just a regular SE and not an SE FDHD/SE SuperDrive model, you cannot use a 1.4 MB drive. it will only function as an 800k drive unless you have upgraded SE ROMs and SWIM chip in place of the IWM chip in the regular SE.
Thanks for this.
There was a 1.4MB floppy in the SE and I shall have to check for the presence of the SWIM chip on the SE motherboard. It could be that mixed & matched floppy drives in the past.
 
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