05-15-2018, 11:19 AM
(This post was last modified: 05-15-2018, 11:25 AM by Fats Drywaller.)
A warning about rogue USB SD-card readers
Was reading some old threads about SD cards & Resmed data & reading the cards on a computer, and here's a bit of trivia that might be of interest to some folks as a potential gotcha: Various cheapie SD-to-USB adapters out there don't pay attention to the write-lock tab and pass that setting along to the USB driver. For instance, an SD-reader stick that was recommended in one thread here is the IOgear GFR204SD, which I also bought a long time ago because it's nice and cheap, but it's one of the offenders. Another offender is the Targus TGR-MSD500, and I'm sure there are more.
That's something to be aware of, because various operating systems do write stuff to the SD card if it's unlocked. So then when you put the card back into the CPAP machine, the machine's firmware might insist on erasing the file system because it has been contaminated by the OS pooping on it.
There are instructions elsewhere (can't remember) for deleting the contamination that Windows puts on the card. On Mac OS, the items to nuke are the directories .Trashes and .fseventd (if it exists) along with the file ._.Trashes (all at the top level). Also the notorious .DS_Store files and whatever else is obviously Apple poop.
That's something to be aware of, because various operating systems do write stuff to the SD card if it's unlocked. So then when you put the card back into the CPAP machine, the machine's firmware might insist on erasing the file system because it has been contaminated by the OS pooping on it.
There are instructions elsewhere (can't remember) for deleting the contamination that Windows puts on the card. On Mac OS, the items to nuke are the directories .Trashes and .fseventd (if it exists) along with the file ._.Trashes (all at the top level). Also the notorious .DS_Store files and whatever else is obviously Apple poop.
