SD Card Error (Nothing new)

[justMongo]

I thought I would relay last night's experience.

I was ready for sleep with mask on; I pressed start.
My ritual is to do a spot SpO₂ check before closing my eyes.
But wait -- that's not my "normal" reading with pressure.

I felt for venting air at the mask -- nada.

I looked over at my S9 and the display was still lit with some message I could not read from my position.
I got up and read it: "SD Card Error, Remove Card and resume Therapy".

I pulled the card and put one of my spare 2GB Transcend cards into the machine.
After it formatted the card to its liking, everything worked well.

I'm going to see if I can diagnose the stock ResMed card...

[Crimson Nape]

You triggered something I hadn't seen in years. . . well since FAT was a common format.   File allocation table format only reserves a fixed number of file name locations. This is regardless of the file size. You can have a bunch of files 1K in size and have your system freak-out with gigabytes of storage available.

[justMongo]

CN -- I was thinking about that. For 2GB and under FAT is the old FAT16. That results in 32kB clusters.
To my recollection, the root directory was limited; but not subdirectories. I may be wrong; but that's what I recall.

Before FAT16 was FAT12 (a byte plus a nibble); that was for the old 360k 5.25 inch floppies.

[Crimson Nape]

Mongo, You're a jinx! My card was working fine until you broke yours.

It has been a few days so I downloaded my data from my WiFi card this morning, only to find it didn't record last night.  I took it out of my S9 and looked at it the data on the computer. Sure enough nothing was there.  I put it back in the S9 and got the format message.  .  .  an hour later the message was still there.  I finally had to format the card twice then let the S9 do its thing, then put the WiFi stuff back on it.  It's now appears to be working.  Tonight will be the test.