SD card limit and fix

[SUSGOD]

I tried to transfer 416 MB of 400 E-Books in formats .PRC, MOBI, .TXT, and .PDF to a Transcend TS2GSDC SD card. I loaded 150 books alphabetically A-F of all formats but then the transfer stoped. I got the message “the directory or file cannot be created”. Only 112MB loaded onto the 2GB card. The e-book reader will accept 2GB SD.

Next I cleared the SD card, inserted it in the e-book reader SD slot and connected the e-book reader to my computer. I tried to load the 400 E-Books on to the SD card again going through the e-book reader. The SD card only took the first 150 e-books or 112 MB leaving 1,854MB free and unused.

I tried using a PNYSD card and had exactly the same problem I have with the Transcend brand. One SD card mfg service Rep suggested “Your e-book files are corrupted. It is possible not all the files, it could be one. To fix this problem you need to run chkdsk at the memory device where are the ebook files.” The e-book files are stored on my PC hard drive and on the SD cards. I ran chkdsk, but there were no corrupted files.

Then I tried to transfer 682 image files to the SD cards, and 606 MB loaded without a problem. The problem seems limited to e-book files. Since both cards had no problem loading image files, I next divided my e-books into folders and loaded each folder. IT WORKED!

SD cards from different manufacturers appear to have a limit on the number of e-books (limit 112MB) that can be loaded directly on to the first level of the SD card. There is no problem loading 425 MB of e-books divided into folders and sub-directories. Fortunately, my e-book reader can use folders.

Why can’t I load all my e-books without folders onto the first level of an SD card? Neither manufacturer could explain this.

PNY 2GB SD card Model#: PSD2GBEF
Transcend 2GB SD card Model#: TS2GSDC

[Dave_S]

Originally Posted by SUSGOD

I tried to transfer 416 MB of 400 E-Books in formats .PRC, MOBI, .TXT, and .PDF to a Transcend TS2GSDC SD card. I loaded 150 books alphabetically A-F of all formats but then the transfer stoped. I got the message “the directory or file cannot be created”. Only 112MB loaded onto the 2GB card. The e-book reader will accept 2GB SD.

That is because the root directory has a limit on the maximum number of entries available. It is better to put only directories in the root, and then put your files in those directories.
http://support.microsoft.com/kb/120138

If your reader is limited to a maximum of 2 Gigabytes on the SD it is likely limited to only using the FAT16 filesystem, so switching to FAT32 is probably not an option. Actually, any SD card is limited to a maximum of 2 Gigabytes as it requires SDHC to go beyond that.

[theducks]

Originally Posted by SUSGOD

Why can’t I load all my e-books without folders onto the first level of an SD card? Neither manufacturer could explain this.

PNY 2GB SD card Model#: PSD2GBEF
Transcend 2GB SD card Model#: TS2GSDC

Susan
What Dave_S said is true. In general, file systems have limits on "root" folders.
Different FS, different limits., but doing what you did will guarantee that you will hit it sometime (when you don't have the time to make it right Murphy )

It is like putting all your family and friends in the front seat of your car. No room for the driver.
If your reader intended to have all your books in one place, it probably would have one giant file (database) that could only be accessed via special software.

Calibre's author started that way and dumped it.
Slow. A burp and it turns into trash.

[SUSGOD]

Originally Posted by theducks

Susan
What Dave_S said is true. In general, file systems have limits on "root" folders.
Different FS, different limits., but doing what you did will guarantee that you will hit it sometime (when you don't have the time to make it right Murphy )

It is like putting all your family and friends in the front seat of your car. No room for the driver.
If your reader intended to have all your books in one place, it probably would have one giant file (database) that could only be accessed via special software.

Calibre's author started that way and dumped it.
Slow. A burp and it turns into trash.

I just don't understand why SD cards will allow 682+ image files on one level but limit e-books to 150. My old Cybook's SD feature could not read folders, but fortunately my Aluratec can.

[Dave_S]

Originally Posted by SUSGOD

I just don't understand why SD cards will allow 682+ image files on one level but limit e-books to 150. My old Cybook's SD feature could not read folders, but fortunately my Aluratec can.

The limit is not the SD card itself, but the file system used on the SD card. In a nutshell, IF the FAT filesystem is used on your SD card, then the number of entries available in the root of the filesystem is determined at the time the SD card is formatted. The standard limit is 512 entries in the root, so if you got 682+, then whatever you were using to get that was a nonstandard FAT filesystem. You should also note that 512 entries is for the old 8.3 file naming convention, so if you use long filenames you will get much less than 512 files and folders in the root.

Maybe this Wikipedia link can explain what is going on to your satisfaction?

The number of root directory entries available is determined when the volume is formatted, and is stored in a 16-bit signed field, defining an absolute limit of 32767 entries (32736, a multiple of 32, in practice). For historical reasons, FAT12 and FAT16 media generally use 512 root directory entries on non-floppy media. Other sizes may be incompatible with some software or devices (entries being file and/or folder names in the original 8.3 format)

http://en.wikipedia.org/wiki/File_Allocation_Table

[SUSGOD]

Originally Posted by Dave_S

The limit is not the SD card itself, but the file system used on the SD card. In a nutshell, IF the FAT filesystem is used on your SD card, then the number of entries available in the root of the filesystem is determined at the time the SD card is formatted. The standard limit is 512 entries in the root, so if you got 682+, then whatever you were using to get that was a nonstandard FAT filesystem. You should also note that 512 entries is for the old 8.3 file naming convention, so if you use long filenames you will get much less than 512 files and folders in the root.

Maybe this Wikipedia link can explain what is going on to your satisfaction?

http://en.wikipedia.org/wiki/File_Allocation_Table

Thank you for explaining it! My image files conform to the old 8.3 file naming convention. The downloaded or created e-book files do not. Now it makes sense.

Susan