USB shown having CDFS filesystem

Hello guys,
I have here a Kingston Datatraveler 4GB USB 3 which when I use it on AmigaOS 4 computers is visible, but not writeable. The system shows that it has CDFS and the size of the USB disk is wrong.

Tried to format by media toolbox, but it didn't work, as it believes it is a CD. Tried to change it's FS from USB MassStorages utility (CTRL + ALT + m) but it is not possible to format it or change it's FS.

Any clue how I can format it to NTFS or FAT, without put it to any PC?

Thank you for your ideas and help.

Isn't it write protected ?

@k-l
It seems write protected, because of the FS AmigaOS recognises. This is my guess.

@walkero

Once something similar happened to me too. It was a new SD card, and I could not format it. I managed with Linux on the AmigaOne, but some time later it had write errors and the issue reappeared. I could not format on a PC either. The only way was with the official SD card tool from sdcard.org (on a mac) after using that I could format on Amiga too. But eventually I found out the SDcard was defective as it took ages to write files to it.

So maybe try with Linux on the A1

@walkero

CDFS filesystem sounds like the stick is formatted for a mac as OS4 HFS support is built into CDFS and being 4GB it's the right size for a DVD-R etc.

probably easiest to get something like this:

https://www.amazon.co.uk/TRIXES-Adapte ... nes-Tablets/dp/B01AWJSVZY

then you can plug the card into your phone/tablet and 'erase' it.

@walkero
Does USB MassStorage Commodity show more than one partition on the flash drive? Years ago I bought a Kingston flash drive that had 2 partitions; a small CDFS partition with security software and a large FAT partiton. I couldn't write to the CDFS partition but the FAT partition worked normally.

Here is a link to a post about similar issues: https://www.techadvisor.co.uk/forum/he ... at-cdfs-usb-drive-4257109

If my 2 partition flash drive was plugged in when I turned my system on, it was recognized as a CD but my system attempted to read from the FAT partition. When I copied my System partiton to the FAT partition and plugged the flash drive in before cold booting, my system recognized it as a CD but booted from the FAT partition. That was before OS4 was supposed to be able to cold boot from USB!

If your flash drive only has a single partition, then it would probably be easier to get a cheap new flash drive than struggling to get the 4GB flash drive working.

It isn't one of the newer "InstallCD" prepared devices is it ?

I have come across several variations of this where a USB device will appear as a physical CD (not actually but the hardware appears as such) until the device is accessed and given a special command to "switch off" the CD Emulation and switch over to the full device capabilities.

I first encountered this using a cellullar modem with a Linux machine some years ago.

just something to think about as the "CDFS" may actually BE a full "Virtual CD ROM" using on-device read-only storage until "flipped over" to "full access" mode...

I would have to lookup what I did for the Linux machine again as there is a more proper term for this.