A fun BeOS story from the 1999 Be Newsletter: https://www.haiku-os.org/legacy-docs/benewsletter/Issue4-22.... A Testing Fairy Tale Two test engineers were in a crunch. The floppy drive they were currently testing would work all day while they ran a variety of stress tests, but the exact same tests would run for only eight hours at night. After a few days of double-checking the hardware, the testing procedure, and the…
> The angled sunlight triggered the write-protection mechanism How does that even happen?
Probably similar to how optical key-switches work: the floppy drive would shine a laser or LED through the write-protect notch and watch for it on the other side with an optical sensor to know whether the disk was write-protected.
So, in a not-write-protected disk (no through-hole), the laser light couldn’t make it through to the sensor... but sunlight sneaking in through the drive casing and under the disk still could.