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Dr.Strange
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Default SD card problems.

I have several SD card issues that hopefully someone can help me with.

First, I have an 8gb card, but only 7.3 of it is accessable. I have a micro SD card reader, and Gparted. Re-formatted the card a couple of times, and it always comes up as 7.3gigs.

Second, when I rooted my phone, I used the Recovery image Ivanmmj has in the stock 1.5 to root thread here on this forum. Shortly after, I think when I flashed ClockworkMod Recovery, I lost the ability to get into recovery by holding volume up and power. Only volume down and power gets me into a recovery state.

Third, I went into ADB and entered some commands from other places to do stuff to the Sd card, but one command still lingers when I do backup or restores:

E:can't mount /dev/block/mmcblk0p2 No such device.

Either that command is blocking off a section of my SD card, or the card just has a bad sector... Any ideas guys?
 
mjgdroid
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Quote:
Originally Posted by Dr.Strange View Post
I have several SD card issues that hopefully someone can help me with.

First, I have an 8gb card, but only 7.3 of it is accessable. I have a micro SD card reader, and Gparted. Re-formatted the card a couple of times, and it always comes up as 7.3gigs.

Second, when I rooted my phone, I used the Recovery image Ivanmmj has in the stock 1.5 to root thread here on this forum. Shortly after, I think when I flashed ClockworkMod Recovery, I lost the ability to get into recovery by holding volume up and power. Only volume down and power gets me into a recovery state.

Third, I went into ADB and entered some commands from other places to do stuff to the Sd card, but one command still lingers when I do backup or restores:

E:can't mount /dev/block/mmcblk0p2 No such device.

Either that command is blocking off a section of my SD card, or the card just has a bad sector... Any ideas guys?
was gonna say card has bad sector, or clockworkmod has a signiture for that file space like a partition, I have read that clockworkmod does this to phones, this is one reason why they brick, and we are told not to use clockwork for this very reason. there are some very nice features in clockwork mod, but for recovery its best to stay with amonra and use the update.zip to change to clockwork if you need to i have included the update.zip
Attached Files
File Type: zip update.zip - [Click for QR Code] (810.2 KB, 24 views)
 
cstone1991
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I have never seen an 8gb card with 8gb accessable. It doesn't sound like anything is wrong here as far as the capacity of your card. My 8gb card has only 7.3 accessable as well. It is standard for any storage medium wether it be an sd card or computer hard drive.

As far as the volume up issue, it has always been volume - for both my phone and my girlfriend's phone. I used the Eris Root For Dummies method for my phone and the One Click Universal Root Method for my girlfriend's. Volume + and end never worked for either phone. Don't know why, but I can get there reguardless.

Hope this helps some.
 
blindmanpb
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Quote:
Originally Posted by Dr.Strange View Post
I have several SD card issues that hopefully someone can help me with.

First, I have an 8gb card, but only 7.3 of it is accessable. I have a micro SD card reader, and Gparted. Re-formatted the card a couple of times, and it always comes up as 7.3gigs.

Second, when I rooted my phone, I used the Recovery image Ivanmmj has in the stock 1.5 to root thread here on this forum. Shortly after, I think when I flashed ClockworkMod Recovery, I lost the ability to get into recovery by holding volume up and power. Only volume down and power gets me into a recovery state.

Third, I went into ADB and entered some commands from other places to do stuff to the Sd card, but one command still lingers when I do backup or restores:

E:can't mount /dev/block/mmcblk0p2 No such device.

Either that command is blocking off a section of my SD card, or the card just has a bad sector... Any ideas guys?
There is nothing wrong with your SD card.

Hard drive, SD card, and USB thumbdrive manufacturers typically define megabytes, gigabytes, etc as incrementing by powers of 1000. (so 1GB = 1000MB)

Most operating systems & software define megabytes, gigabytes, etc as incrementing by powers of 1024. (so 1GB = 1024MB)

So according to the manufacturer, your SD card has a capacity of 8GB (8000MB)
According to any operating system (Android, Windows, OSX, Linux, etc), your card has a capacity of 7.8GB (8000MB / 1024)

When you format ANY storage medium (hard drive, SD card, etc), the stated capacity of the device and the available capacity will not be the same.

To make matters worse, some of that 8GB/7.8GB (depending on how you measure) has to be used by the file system to figure out exactly where all of your files are being stored on the card.

I don't know if you ever had to use a card catalog system in a library, but think of it this way.
Let's say you build a library capable of holding a thousand books. However, you're not going to arrange the books according to author's names, titles, or the Dewey Decimal System. You're just going to stick them on shelves in whatever order you get them in.
Whenever you need to find a particular book, you're going to need some way of figuring out exactly where it is in the library. So you'd need a card catalog of sorts. This card catalog is going to take up some of the room in your library, meaning you won't be able to store EXACTLY 1000 books anymore.

Okay, it might not be the best analogy in the world, but it's late here and I hope it gets the point across.

From wikipedia: "A general rule of thumb to quickly convert the manufacturer's hard disk capacity to the standard Microsoft Windows formatted capacity is 0.93*capacity of HDD from manufacturer for HDDs less than a terabyte."

So out of that 7.8GB of space, you're only going to be able to use about 7.3GB of it (7.8 * 0.93).
 
blindmanpb
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Oh, and as for
"E:can't mount /dev/block/mmcblk0p2 No such device. "

I'm not too certain about this, but i believe /dev/block/mmcblk0p2 is the mounting point for apps2sd partitions, assuming the ROM supports them, and if you're running a stock ROM, it won't.

Your recovery image does though, so every time you do a nandroid backup/restore, it checks for an existing partition for apps2sd. Since it doesn't exist, it shows that message. Nothing to worry about.

Hopefully someone who knows a bit more about it can explain it better, but I don't believe that's an actual error in this case.

I do know it doesn't have anything to do with your 8GB/7.3GB issue though.
 
stevesk
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Did you try partitioning it on your phone to 0? That worked when I had a similar problem.
 
deden19
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i have phone xperia acro SO-02s..when i put SIM card+SD card,the SD card not detected,but when i take SIM card and put SD card..my SD card is working,,please help me.thanks

 
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