A trivia not touched on in the article - IBM 5 1/4" floppy drives had dual heads and could read the front and back side of a disk without flipping. For cost savings Apple ][ drives had only one head so you had to flip the disk occasionally. But to convert an IBM 5 1/4" floppy for dual sided used on an Apple, you had to cut a second write-protection notch, either with scissors, and xacto-knife, a hole punch, or with a dedicated "drive doubler" puncher.
The original IBM PC could be purchased either with 160KB/180KB single-sided floppy drives, or the 320KB/360KB double-sided. Some early IBM PC users still needed the "flippy" trick!
As a kid (ok, as an adult too), I knew what the "CH" on floppies meant. I was curious, but never asked or tried looking it up.
I forget when, but one day, it dawned on me that it said "HD"!
I guess most of my floppies had their labels on in such a way that the flap/door was facing down, so it said "CH". To read "HD," then the label would be upside down.
One thing I really miss with flash drives, a write protect switch.
Yes, I can mount 'ro', but many (all?) Linux Desktops mount the drive write through its GUI. I have aliases for mounting and never used the pointy-clicky mount in DEs.
FWIW, I am usually in fvwm or cwm, depending on screen size, so I mount 'ro' when I want to. But a hw switch on flash drives would have been nice :)
With the default ext4 filesystem, mounting 'ro' doesn't actually prevent writes to the disk. For that you need 'noload' too, to prevent journal replay. This can result in a broken filesystem if it wasn't unmounted cleanly, although assuming it's 100% read-only it shouldn't do any permanent damage (perhaps enforce read-only access at the block device level to be sure).
I thing I learned only recently is that the write protect switch on the SD card is not an electrical switch connected to anything in the SD card itself: it just hits a lever in the SD socket that opens a contact closure and it's up to the system (hardware and software both) to bother to look at it. So on many systems the write protect switch doesn't even work.
A trivia not touched on in the article - IBM 5 1/4" floppy drives had dual heads and could read the front and back side of a disk without flipping. For cost savings Apple ][ drives had only one head so you had to flip the disk occasionally. But to convert an IBM 5 1/4" floppy for dual sided used on an Apple, you had to cut a second write-protection notch, either with scissors, and xacto-knife, a hole punch, or with a dedicated "drive doubler" puncher.
https://atariprojects.org/2019/06/28/make-floppy-disks-doubl...
The original IBM PC could be purchased either with 160KB/180KB single-sided floppy drives, or the 320KB/360KB double-sided. Some early IBM PC users still needed the "flippy" trick!
See IBM advert, https://archive.org/details/eu_BYTE-1983-10_OCR/page/n111/mo...
Same for the C64 floppy drive (1541).
As a kid (ok, as an adult too), I knew what the "CH" on floppies meant. I was curious, but never asked or tried looking it up.
I forget when, but one day, it dawned on me that it said "HD"!
I guess most of my floppies had their labels on in such a way that the flap/door was facing down, so it said "CH". To read "HD," then the label would be upside down.
I still have a few floppy disks packed away at the loft, but I wonder if they still work the next time I turn on my BBC or Archimedes.
The last time I checked, the only 5,25" floppies that still worked from that age were the ones in those Acornsoft covers.
I just feel like tech moved so fast that in SOME ways its sad.
I just wish we could still use retro tech in some way without having to replace it.
One thing I really miss with flash drives, a write protect switch.
Yes, I can mount 'ro', but many (all?) Linux Desktops mount the drive write through its GUI. I have aliases for mounting and never used the pointy-clicky mount in DEs.
FWIW, I am usually in fvwm or cwm, depending on screen size, so I mount 'ro' when I want to. But a hw switch on flash drives would have been nice :)
With the default ext4 filesystem, mounting 'ro' doesn't actually prevent writes to the disk. For that you need 'noload' too, to prevent journal replay. This can result in a broken filesystem if it wasn't unmounted cleanly, although assuming it's 100% read-only it shouldn't do any permanent damage (perhaps enforce read-only access at the block device level to be sure).
You might like: https://www.kanguru.com/products/kanguru-ss3
Using an SD card (or micro SD in an adapter) connected to a USB reader might meet your needs. You can then use the SD write protect switch.
I thing I learned only recently is that the write protect switch on the SD card is not an electrical switch connected to anything in the SD card itself: it just hits a lever in the SD socket that opens a contact closure and it's up to the system (hardware and software both) to bother to look at it. So on many systems the write protect switch doesn't even work.
I only see a 403
https://web.archive.org/web/20251002092405/https://retrocmp....