Lexar 128GB SDXC - Who's going to be first on this?


Which instruction mentions "sudo fdisk /dev/mmcblk0p1"? That is simply wrong and should be corrected. "p1" is the partition and is not supposed to be modified with fdisk (to my knowledge). "mmcblk0" is the whole card (if it's the first card that was inserted. If inserted second, then it's "mmcblk1"). Also the card must not be mounted when working with fdisk on it.
 
Is there a typo in my post, someplace else, or just a misunderstanding of the directions?


If there is something wrong there I can fix it.


I hadn't wanted to leave an exact "sudo fdisk /dev/mmcblk0p1" in my directions because I wanted somebody to think about what they were doing and not to just blindly follow my steps and then wipe out a card with working data on it.
 
Hello NearTao.


After writing my reply, i searched for your instructions and read it. As far as I can tell, your instruction is correct. So it was a misunderstanding. The only proposals I want to make are:


- maybe add a section, that explains about mmcblk0 being the first card inserted and mmcblk1 being the second card that has been inserted. The numbers are NOT bound to the left and right card-slot. Since you can easily lose the complete content of the wrong card, this is worth mentioning. The safest option is to remove the card that you do NOT want to format, if this is possible (i.e. you are not booting from SD-card).


- you should mention to delete any possible existing partition within fdisk by using "d".


- the card must not be mounted while using fdisk
 
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Sorry for the confusion... I was referencing this:

...


For the next steps replace /dev/sda with whatever your device is (probably /dev/mmcblk0 or 1) and replace /dev/sda1 with whatever your partition is... /dev/mmcblk0p1 or /dev/mmcblk1p1.


...

After reading the last few posts I realized what I did wrong initially. I've been using linux for a few years, but fdisk isn't something I've used very often. You do still have to use "sudo" for fdisk on the Pandora, correct? I've never gotten fdisk to work on any other system without it. I know the mkdosfs didn't work without sudo for me.


EDIT: Spelling
 
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You do still have to use "sudo" for fdisk on the Pandora, correct?

Correct. Commands like "fdisk" and "mkfsdos" need to be executed as root. This can be achieved by either running each command through "sudo" (like "sudo fdisk") or by switching to the root-user constantly in the current terminal by executing "sudo su" for example. Once you did the later, you can just run the commands without "sudo" in front of them. Keep in mind that the root user is allowed to do almost anything. So you can also destroy almost anything. Also some things you do not want to do as root. For example if you copy files as root, then newly created files get root-rights and are likely not to be accessible as normal user.
 
So - if you have one of these 128GB cards - can you run the read-only benchmark from the wiki and post back here?


Thank you!
 
So - if you have one of these 128GB cards - can you run the read-only benchmark from the wiki and post back here?

I was gonna run the write benchmark first, but I discovered I didn't remember my Pandora passwords, either mine or root's. :(


If you tell me how I can reset my password I'll run read and write benchmarks on it.
 
In general you should be able to change/reset the passwords by booting from an sd-card with a system where you KNOW the passwords ;) , mount the filesystems of the system where you forgot the passwords (mounting the 2nd SD-card shouldn't be a problem. mounting the nand: http://pandorawiki.org/Running_Linux_from_an_SD_card#Access_the_NAND), chroot to it and run "passwd".


If you need a more detailed description better open a separate thread in the support-section.
 
I have one of these on the way.


http://www.bhphotovideo.com/c/product/756124-REG/Lexar_LSD128CRBNA133_128GB_Professional_SDXC_Card.html


$165 is the best price I'd seen on it. It should arrive sometime next week.


However, there is a newer & faster one just starting to appear...


http://www.bhphotovideo.com/c/product/841484-REG/Lexar_LSD128CTBNA400_128GB_SDXC_UHS_1_MEMORY_CARD.html


$253 is outside my price range for one of these, and I doubt the Pandora could take advantage of the additional speed. I wonder just how much faster it really is.


Fun stuff.
 
I have one of these on the way.


http://www.bhphotovi..._SDXC_Card.html


$165 is the best price I'd seen on it. It should arrive sometime next week.


However, there is a newer & faster one just starting to appear...


http://www.bhphotovi...EMORY_CARD.html


$253 is outside my price range for one of these, and I doubt the Pandora could take advantage of the additional speed. I wonder just how much faster it really is.


Fun stuff.

so does it work on the pandora? I want to know if I shoulld get one.
 
so does it work on the pandora? I want to know if I shoulld get one.

I have one and it works on the Pandora. In fact it's playing music off of it right now. No battery life issues, but I haven't run a dd test on it. If you want me to I can.
 
I benchmarked the SCXC 133x 128GB Lexar card extensively in this thread:





I have one of the SDXC 400x 128GB Lexar cards on the way - should ship today. I'll probably benchmark it on the Pandora, but it's real purpose is use in a camera.
 
I tried ext4/3 to no avail

When formatting ext2/3/4 it puts inode tables all over the partition, a side-effect is that it tests it can write to regions near the end. FAT quick format does not do this. If it fails to format with ext, that likely means part of the device is not addressable. Formatting with ext can also be a quick way to check whether you were sold a fake undersized SD card.


So yeah, I'd like to know if you were able to put at least 100GB of data on one of these, and if the Pandora can read and write it.
 
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I tried ext4/3 to no avail

When formatting ext2/3/4 it puts inode tables all over the partition, a side-effect is that it tests it can write to regions near the end. FAT quick format does not do this. If it fails to format with ext, that likely means part of the device is not addressable. Formatting with ext can also be a quick way to check whether you were sold a fake undersized SD card.


So yeah, I'd like to know if you were able to put at least 100GB of data on one of these, and if the Pandora can read and write it.

Yes and yes. You have to use a format that the Pandora can read though. From my fiddling, testing, etc., I decided that ext2 worked best for my 128GB card on the Pandora. Your experience may differ.


There is no issue with recording 100+GB to the card in ext2 and no issue reading it on the Pandora. Just keep in mind that reading/writing 100GB on a device that reads at ~17MB/sec and writes at 10+ is going to take a while.
 
Ok, so maybe you guys can help me. I just got the SanDisk 128GB card (3.3v if that helps) and I followed the directions given by Toa up to a point. I updated dosfstools proper and ran sudo fdisk /dev/mmcblk0 which works except for one thing. it reads my other sd card which is a 4 GB card. I tried chanching it to


sudo fdisk /dev/mmcblk1 but it just says that it is unable to open it, which makes me think the card is either not being read or i dont know the proper name for it. I'll be honest, i pretty much rely on other people to know these things. I know the is real and not broken because I bought it from a reputable store and i tested it out on severl other devices, although i havent run any tests since my actual laptop is comatose at the moment. I could probably format it easily if it wasnt but it is, so im stuck with doing it on the pandora.


basically if anyone can help with this issue itd be great. I just want to format it to fat


EDIT: I figured it out. I had to use the full path /dev/mmcblk0p1 and it worked like a charm.
 
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Just a quick question. I have yet to figure out how to successfully format the sd card to ext2 (although I would gladly take instructions for that in lieu of what i'm about to ask). I have been able to formt it to FAT32 but only with a single partition, which has caused it to, basically, fuck up every time I tried to use it to get files from my brothers computer, the only computer at my dispsal, whiich is a windows 7.


So my question is, how many partitions do I need to make in FAT32 and to what specifications?


EDIT: I may not need that help after all, but I did find a thread for anyone else that may be running into the input/output error that I kept running into when writing large amounts of data to my new sd card.





I'm going to try this. If it doesn't help then i guess I will have to deal with it. I may have broken the card anyway from repartitioning it a million and a half times in a row without addressing that error. hopefully I can clean it up, though.
 
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