(How To) CM7 Bootable SD

Stumblethru

Member
Feb 12, 2011
31
2
I've just been playing around with free RM and CWR, they don't seem to do much being on the card. The only thing I got to do anything was the "fix permissions".
 

trjcasper

Member
May 17, 2011
8
2
Thanks J515OP!

Another question, can someone recommend what brand/class/size card is good for running CM7 from? I've tried a 2GB PNY and there is a lot of lag, occasional force close/wait messages, and web browsing was so slow it was unusable.

The XdA folks on the forums have figured this out. They've been benchmarking the sd cards and finding that the "higher quality/speed/class cards suck for booting into sd. A lowly San Disk class 2 - 8GB card is actually better. see link SD Strange-results - or - How I learned to love CM7 - xda-developers
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
899
The XdA folks on the forums have figured this out. They've been benchmarking the sd cards and finding that the "higher quality/speed/class cards suck for booting into sd. A lowly San Disk class 2 - 8GB card is actually better. see link SD Strange-results - or - How I learned to love CM7 - xda-developers

Your post is misleading. That thread doesn't give conclusive evidence that higher class cards will run bootable SDs slower than lower class cards. What it really says is that small bock Random Write speeds are important to running an OS from a bootable SD. Out of the cards tested the SanDisk cards seem to have the best small block Random Write speeds regardless of the class of the card.

This link gives the better measure based on that criteria http://forums.whirlpool.net.au/archive/1582172. As you can see from post #32 in the XDA thread the SanDisk Class 4 stomps on the SanDisk Class 2 in the same post. Brand is probably more important than class with SanDisk seeming to be the best in this catagory. But it also appears there is a mtter of luck in the performance of the Random Write speeds of a given card.

mcb01 said he was experiencing slowness but was using a class 2. The problem probably wasn't that it was a class 2 but that it was a PNY.

trjcasper, thank you for your post. Sometimes things aren't what they appear to be on the surface but with a little digging the answers are in the info you provided :D
 

kashif977

Member
May 9, 2011
19
2
J5150P, Thank you so much for this information. This has been my first experience with booting with CM7 on SD and with your instructions its been breez. I really love it and I was so happy to do it right the first time. Thanks again.

Can you please tell me the difference between CM7 and Autonooter? Thanks
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
899
J5150P, Thank you so much for this information. This has been my first experience with booting with CM7 on SD and with your instructions its been breez. I really love it and I was so happy to do it right the first time. Thanks again.

Can you please tell me the difference between CM7 and Autonooter? Thanks

Good to know you got CM7 running it is a nice ROM for the Nook. This explains the differences between the ROMs http://www.androidtablets.net/forum/nook/14586-android-roms-nook-color-info.html. Basically autonooter is rooting (or unlocking) the B&N ROM that is already on the device. CM7 is a standalone custom ROM built on Android 2.3 and has nothing to do with the original B&N ROM.


JP
 

trjcasper

Member
May 17, 2011
8
2
Your post is misleading. That thread doesn't give conclusive evidence that higher class cards will run bootable SDs slower than lower class cards. What it really says is that small bock Random Write speeds are important to running an OS from a bootable SD. Out of the cards tested the SanDisk cards seem to have the best small block Random Write speeds regardless of the class of the card.

This link gives the better measure based on that criteria http://forums.whirlpool.net.au/archive/1582172. As you can see from post #32 in the XDA thread the SanDisk Class 4 stomps on the SanDisk Class 2 in the same post. Brand is probably more important than class with SanDisk seeming to be the best in this catagory. But it also appears there is a mtter of luck in the performance of the Random Write speeds of a given card.

mcb01 said he was experiencing slowness but was using a class 2. The problem probably wasn't that it was a class 2 but that it was a PNY.

trjcasper, thank you for your post. Sometimes things aren't what they appear to be on the surface but with a little digging the answers are in the info you provided :D
Digging deeper in that thread to post #87 shows a class 2- 8 GB sandisk stomping all others. I bought one yesterday and it benchmarked very similar numbers to that card on the chart posted. My nc has gone from slow to superstar.
It certainly wasn't my intention to mislead, I found information that I was able to replicate. I figured it was helpful given the number of people who are having issues with good quality cards that don't perform to expectation hen booting fromsd. I personally thought CM7 was glitchy. Not so. It was related to the sd I was using.
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
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I think it is a good post and good link to info and I will actaully make a note in the instructions. Just wanted to warn others about being careful of just jumping to the lowest class card possible since the post specifically says higher class cards suck and a lowly class 2 is better. Being a SanDisk probably has more to do with it than being a class 2.

For the record the key factor is small block Random Write (QD32) speed when considering a micro SD to use for running a bootable OS, not card class. Post #87 in the XDA thread contains the most up-to-date listing as of the time of this post with the results being that SandDisk Class 4 cards are generally your best bet for getting a high performance QD32 speeds.

Thanks again to trjcasper for bringing up the issue. :)
 

CLSmith

Member
Jan 14, 2011
106
0
Hi, I am going to give this a try.
Currently running-stock1.1 autonootered (I don't know which version) CWM 3.0.2.8 (how do you tell where it's installed? and is that important?) Rom Manager 4.2.0.2 )Still not sure how to use this, but good at following written instructions) SD card-Scan Disc 8G Cls 4

I downloaded the 3 files (steps 1-3) They went to my Download file folder, which is not the root of C:/. Do I need to move these files to 'C' root? If I need to move them, do I just copy or redownload them?
Step 1: How do I unzip the file? How do I burn a file?
Step 2: I downloaded cm-7.0.2 cause i read it worked better for Netflex. Is this correct?
Step 5a: Do I want to put this file (overclock kernel) not sure where to get this from, on the card with the other 3 files, before I boot CM7?

Enough questions for now, you guys are great! Thanks for the education.
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
899
Hi, I am going to give this a try.
Currently running-stock1.1 autonootered (I don't know which version) CWM 3.0.2.8 (how do you tell where it's installed? and is that important?) Rom Manager 4.2.0.2 )Still not sure how to use this, but good at following written instructions) SD card-Scan Disc 8G Cls 4

I downloaded the 3 files (steps 1-3) They went to my Download file folder, which is not the root of C:/. Do I need to move these files to 'C' root? If I need to move them, do I just copy or redownload them?

Where the files go on your computer is not important. You may move the files as you wish on your PC without redownloading them. What is important is where they go on the SD card when you copy them over from your PC. They should go on the main part of the SD card (not in any folder) which is called the root, after you burn the .img file to the card.

Step 1: How do I unzip the file? How do I burn a file?

To unzip a file you need a zip program such as 7zip or Winzip. Just google "unzip program" and you will be presented with may options. Once you have found one you like and installed it, use it to unzip the file (in this case the .img file in #1).

You also need a program to burn an image such as Win32DiskImager. Once you have unzipped the file and installed the imager program, open the program and point it to the file you want to burn (the unzipped file from #1) and the location to bun it to (the SD card). The interface for these programs is pretty simple and these are the only two options you should really see.

Step 2: I downloaded cm-7.0.2 cause i read it worked better for Netflex. Is this correct?

I haven't heard that. Persoanlly I would go with the most recent version of CM7.

Step 5a: Do I want to put this file (overclock kernel) not sure where to get this from, on the card with the other 3 files, before I boot CM7?

The overclock kernels can be found in the links in this thread http://www.androidtablets.net/forum...honeycomb-dalingrins-oc-kernel-2-25-11-a.html. YOu want to make sure you choose a CM7 SD kernel (by default CM7 is overclocked to 925MHz so this is entirely optional). The files does go on the card before you boot for the first time as does the CM7 file and gapps file.
 

ShutterPeep

Senior Member
May 3, 2011
149
8
I can't get Bluetooth to work running 7.0.3 via SD. It just says Turning on but never does. I've tried a reboot as well as a hard reset but it hasn't been rectified. Can anyone point me in the right direction? I actually want to tether to my iphone via BT since I've got a data plan.

TIA!
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
899
I can't get Bluetooth to work running 7.0.3 via SD. It just says Turning on but never does. I've tried a reboot as well as a hard reset but it hasn't been rectified. Can anyone point me in the right direction? I actually want to tether to my iphone via BT since I've got a data plan.

TIA!

Why not tether via wifi?
 

CLSmith

Member
Jan 14, 2011
106
0
Thanks J5 for your help. I'm working on it right now, downloading CM7 7.0.3

Do I need to format the SD card before I put any files on it? And do I format the card in my PC or Nookcolor?
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
899
If you are starting with a clean SD card (one that hasn't had an image burned to it) you don't need to format it but it wouldn't hurt. I personally like to format the SD cards in my Nook but the PC will work too.
 

J515OP

Super Moderator
Staff member
Jan 6, 2011
5,172
899
I'm only using a 3GS model which has bluetooth and USB as options for personal hotspot unlike the iPhone 4.

That can be "fixed" if you jailbreak. Have you looked into the standard bluetooth tricks? They are spread around in a few different threads so try a search. One I do recall is that you may have to turn wifi off, reboot, trun bluetooth on then turn on wifi.

JP
 
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