Floppy write protect question

[dittman]

8" floppies require the notch to be covered to enable writing to the disk.

5.25" floppies require the notch to be uncovered to enable writing to the disk (and 3.5" drives require the hole to be uncovered to enable writing to the disk).

I've always wondered why this was reversed when the 5.25" format was created but never heard an explanation.

Does anyone know why?

 

[Stone]

5.25" floppies require the notch to be uncovered to enable writing to the disk (and 3.5" drives require the hole to be uncovered to enable writing to the disk).

No, 3½" disks are write protected when the hole is uncovered. They require the hole to be covered to write to the disk.

 

[Chuck(G)]

I've always wondered why this was reversed when the 5.25" format was created but never heard an explanation.

Does anyone know why?

Practicality. You can manufacture write-protected 5.25" floppies that cannot be write-enabled easily, yet it's easy to manufacture write enabled floppies just as easily. When software began to be distributed on floppy, this became important. The same idea obtains for 3.5" floppies--produce them leaving out the write-enable slider and you have a write-protected floppy without having to change your production equipment.

 

[dittman]

No, 3½" disks are write protected when the hole is uncovered. They require the hole to be covered to write to the disk.

That's what I meant to say but wrote the wrong thing. Thanks for catching it.

 

[dittman]

Practicality. You can manufacture write-protected 5.25" floppies that cannot be write-enabled easily, yet it's easy to manufacture write enabled floppies just as easily. When software began to be distributed on floppy, this became important. The same idea obtains for 3.5" floppies--produce them leaving out the write-enable slider and you have a write-protected floppy without having to change your production equipment.

That makes sense.

 

[krebizfan]

Part of the 3.5" floppy design was that Sony used a snap-off read/write tab (like cassettes) before the slide tab was invented. Had to maintain compatibility with the existing drives. http://www.macgeek.org/museum/sony400kdrive/