+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: FlashAir SD Card Failure? (/Thread-FlashAir-SD-Card-Failure)
FlashAir SD Card Failure? - WSHenry - 08-02-2015
Hi,
I really liked the convenience of using the FlashAir SD card along with the Sleep Master utility. It worked flawlessly for several months, but am now back to using a SanDisk Ultra SD card for the last few weeks with no issues.
Here's the narrative from my sleep log:
Installed and started using about 2/15/2015. In use until 7/5/15, and replaced with standard SD card, due to card write failure. The failure was write data from the 7/4/15 - 7/5/15 sleep session. Prior to this, I noticed intermittent failure to capture data (?) from the machine. This occurred occasionally from about 6/15/15 to 7/4/15. As displayed in SleepyHead, that pertained to flow rate, pressure, leak rate, snore and AHI, although events were flagged. Subsequent checks of standard SD card on 7/19/15 and 8/2/15 found all days recorded with all parameters logged and displayed.
Can anyone using a FlashAir card shed some light on this? Any suggestions on what/where to check? I'd really like to go back to accessing the data remotely.
Thanks in advance.
RE: FlashAir SD Card Failure? - AlanE - 08-02-2015
Did you try formatting the card? Save the SD_WLAN folder (or all data) and copy it back after the format. It is possible it is failing. These types of storage medium have a life span. They have so many writes before they become unreliable. I don't know if FlashAir incorporates any type of wear leveling algorithm. It may be you have hit up upon a defective block. Formatting may mark it as unusable.
RE: FlashAir SD Card Failure? - WSHenry - 08-02-2015
(08-02-2015, 09:40 AM)AlanE Wrote: Did you try formatting the card? Save the SD_WLAN folder (or all data) and copy it back after the format. It is possible it is failing. These types of storage medium have a life span. They have so many writes before they become unreliable. I don't know if FlashAir incorporates any type of wear leveling algorithm. It may be you have hit up upon a defective block. Formatting may mark it as unusable.
Alan,
I did a check of the media and Win 7 reported it as ok. I reformatted anyway, reinstalled the data files, reinstalled it in my PRS1 and the problem still existed. I've only had the card for a few months. Worst case would be about 120 read/write cycles. I can't imagine solid state nonvolatile memory going bad after that few cycles.
RE: FlashAir SD Card Failure? - Jack_Russell_Fan - 08-02-2015
I have FlashAir cards that have been in constant use for over 8 months, without failures, but not without a few glitches.
With the cards in my PRS1 760P, every few months SleepyHead will
have a problem with the data for one day. Checked the data with Encore Basic and all is OK. Don't know where the glitch is, but I suspect SH.
The regular windows disk utilities will work on the FlashAir, scan for errors and defrag.
Tom
RE: FlashAir SD Card Failure? - eseedhouse - 08-02-2015
(08-02-2015, 10:46 AM)WSHenry Wrote: I've only had the card for a few months. Worst case would be about 120 read/write cycles. I can't imagine solid state nonvolatile memory going bad after that few cycles.
Things can go wrong for no apparent reason. I had a card a couple of months old go bad. I had it in my laptop and noticed the plastic to right of the keyboard was getting hot. So I reached for the SD card and it burned my fingers! It was HOT. I'd used it without incident quite a few times but it just decided it was time to die, I guess. Couldn't read or write to it after it cooled down, either.
So yeah, stuff happens. Best to have a backup card ready.