Questions tagged [flash-memory]
The flash-memory tag has no usage guidance.
136
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Is DD-WRT wasting NVRAM space?
Please explain how I am misunderstanding these two commands:
root@DD-WRT:/tmp/var/log# cat /proc/mtd
dev: size erasesize name
mtd0: 00080000 00020000 "boot"
mtd1: 00180000 00020000 &...
- 123
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1
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28
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Is it possible to break flash card programmatically?
I think I broke my flash card programmatically while was playing with automount configuration. Now I can't mount my card anuwhere.
Was this possible? And if it was, then how to ensure and fix?
- 3,195
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141
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How is MTD partition layout detected/parsed in Linux?
I am working on an embedded Linux system, which uses kernel-5.10.24.
There is a NAND FLASH used as storage in system, and it has 4 partitons. When the kernel boots up, there shows 4 partitions as ...
- 327
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1
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575
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How to properly erase entire block device /dev/xxxx?
I have a block device that I'm trying to erase using dd. Seems like all my portion has been deleted. However, dd command is returning No space left on device. Block device information is as follows,
...
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1
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771
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Slow file transfer to USB stick
I'm copying files to a USB 3.0 stick. The USB stick is plugged to a blue USB port.
I'm copying 22 files of 1.5GB.
When I do the copy (simple drag and drop), the copy dialog reports a speed of ~60MB/s, ...
- 81
1
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1
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684
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How to write data to raw NAND FLASH through /dev/mtd0 in Linux?
I am working on an embedded Linux system (5.10.24), where there is a NAND FLASH as storage.
The NAND FLASH is partitioned into 4 parts, part 0 is used for u-boot, part 1 is used for kernel, part 2 is ...
- 327
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0
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53
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Enable SPI flash device's power cycle write protection
Assume that an SPI flash chip is represented as /dev/spidev. How do I enable that flash chip's power-cycle write protection?
- 3,838
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34
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cp .iso /dev/sdd usb memory device full
I was informed, from here, the best (easiest) way in linux to put a bootable iso file to a usb stick and have it be bootable to do an install is simply via cp rhel-8.5-x86_64-dvd.iso /dev/sdd where ...
- 5,816
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43
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How to unplug/unmount USB Flash card, which was automounted?
I have configured my flash card to automount with the following lines inf fstab:
UUID=6364-3963 /mnt/Flash03 auto noauto,nofail,x-systemd.automount,x-systemd.device-timeout=2
UUID=3537-3561 /mnt/...
- 3,195
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29
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RHEL8: Cannot read / modify / delete directory
We have a cluster of flash drives (8TB) mounted on /data as per:
/dev/mapper/vg.data-lv.data on /data type ext4 (rw,relatime)
There are a couple of directories inside /data with one being tmp:
ls -...
- 135
2
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0
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125
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Using veritysetup with MTD on embedded Linux. mtd vs mtdblock
[Background]
I am working on an embedded Linux platform trying to setup dm-verity on NAND flash. I am using v2.3.0 of cryptsetup (part of soc vendor's package), and this is my first go at it. With ...
- 21
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1
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443
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Block read and write in NOR flash
Actually i am working with NOR flash. I am getting confused about block read and write from NOR flash.
From my understand block read and write means writing and reading complete sector of the flash. ...
1
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1
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292
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Help with (corrupted?) flash drive
When I plugged in my “old” flash drive to my Windows desktop, it seemed that Windows 10 was unable to read the data on that USB stick. I checked W10's disk management and the drive's filesystem is “...
- 11
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1
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708
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Recover files from hardware failed ssd
I have an ssd that has had a hardware failure of some kind, I can rma it as it is still under warranty but their service does not include data recovery. I have collected my work files from it but my ...
- 103
2
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0
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653
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Reducing flash wear from Systemd Journald (embedded device)
I'm experimenting with Systemd and in particular Journald on a Yocto Poky (Linux) based embedded device with eMMC storage but I'm worried about flash wear since the write stats are excessively high as ...
- 71
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1
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449
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How can i copy data from NAND memory to sd card?
So basically, i have two Gumstix Overo and both are booting from their NAND flash memory, both devices use full linux image's Kernel. They are supposed to boot the same thing but one of them says that ...
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0
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210
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MLC NAND flash support in ubifs in 2021
I would like to ask about MLC NAND support in UBIFS as of 2021.
I was recently bringing up a device with IMX6ULL and raw MLC NAND flash. I have built Linux 5.4 kernel, u-boot and rootfs (using ...
- 101
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1
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1k
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What does fdisk's Start and End values mean when looking at a compact flash
I'm analyzing a compact flash using fdisk and by comparing it to the contents of the partition table on the CF's master boot record. I don't understand what the "Start" and "End" ...
- 129
1
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1
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359
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Unable to mount cloned compact flash after using dd to clone bootable compact flash
I'm trying to clone a bootable 1GB compactflash to a second 1GB complactflash, but when I try to mount it, i get an error like so,
sudo mount /dev/sdb1 /media/frank/cloned/
frank@ThinkPad2:~$ sudo ...
- 129
1
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1
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1k
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Which is the correct mechanism for auto-mounting a USB flash drive at boot?
I'm seeing apparently conflicting information on the proper way to auto-mount USB flash drives at boot. Most instructions on how to do it say to use an entry in fstab. Gnome Disks has a built-in ...
- 673
4
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0
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956
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Can dm-crypt (LUKS2) be implemented on top of an UBI volume on a raw NAND flash?
If I have an embedded system with a raw NAND flash, with a bad blocks table etc., as I understand it, the best way to have partitions is to have have them as UBI volumes on top of MTD. UBI takes care ...
- 185
1
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0
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188
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dd displays progress incorrectly when writing to flash card (faster than actual)
I am writing Raspi images on flash card with the following command
dd bs=4M if=image.img of=/dev/sdf conv=fsync status=progress
and it displays progress
5662310400 bytes (5,7 GB, 5,3 GiB) copied, 25 ...
- 3,195
1
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0
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135
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Prevent filesystem from synchronizing
I have an embedded system running Debian with a ext4 file system on eMMC.
If the power goes down, the system has about 1 second to detect and sync the file system before voltage is below threshold and ...
- 11
2
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0
answers
156
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How to know if embedded linux contains NAND or NOR flash?
Is there any shell command that can find out if embedded linux used NAND or NOR flash?
- 121
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1
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76
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Linux partitioning vs. mount file system declaration
I'm looking a Linux device where blkid shows an eMMC partition type as ext2:
/dev/mmcblk0p32: UUID="1c48ca57-c9eb-4ed1-a51a-212f7d1fd40e" TYPE="ext2" PARTLABEL="configs" ...
- 125
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1
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226
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Format unmountable usb pendrive
I believe someone else has already encountered this very same issue. Yet, I googled a lot and couldn't find my specific case.
Yesterday I created a "password reset disk" in Windows, using a ...
- 121
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0
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41
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How to install a Linux OS in pendrive and use it?
I am currently using UBUNTU in Raspberry Pi4.
I have another PC that has a crashed hard disk. So what I am planning is to get rid of that HDD and use a pen-drive instead. What I am planning is to make ...
- 162
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1
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1k
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Slow transfer/write speed to USB 3 flash. What are all possible solutions?
Please see the following screenshot of transferring to a USB 3 sandisk flash drive:
This has been asked before but the answers didn't help. They always suggest changing this:
echo $((16*1024*1024)) &...
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-1
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1
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46
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Why does the write speed keep changing, on a msdos file-system on toshiba 64Gb USB flashdrive
I have just bought a new 64gb toshiba 2.0usb flashdrive and put 13gb on it that took about 1 1/2 hours to transfer (max). But it started out saying about 7/8mb transfer and went to 1.3mb transfer, ...
- 121
1
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0
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300
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Is it possible to resize MTD partitions at runtime?
I have a very specific need:
to partially replace the content of a flash and to move MTD partition boundaries.
Current map is:
u-boot 0x000000 0x040000
u-boot-env 0x040000 0x010000
kernel ...
- 850
2
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1
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2k
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dd if=/dev/zero leaves drive contents in-tact? Bad USB stick?
I thought I could nuke all partitions of a drive by using dd if=/dev/zero of=/dev/sdX. In the past this has always worked for me, but in this case it is not working as expected.
#check the partitions
...
- 779
2
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1
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11k
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How to manually mount the virtual file systems, to copy MTD partitions
Linux version 2.6.26.5, ARM Linux Kernel on embedded device, NAND-based device. I'm at Busybox rescue shell (ash), with restricted command set.
How to manually mount the virtual file systems, to copy ...
- 121
2
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1
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851
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Replacing busybox in an embedded device
I'm using busybox in an embedded device. The built-in busybox is rather limited.
So I want try to replace busybox in place with new, more complete version. I find some info about replacing Busybox on ...
- 511
1
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1
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686
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Read raw SMART data with smartmontools from CF card
I have a Transcend CompactFlash card; its datasheet specifies the SMART data structure i.e. "Power cycle count" is bytes 115-116 in this structure.
I am running on a custom embedded system with ...
- 111
1
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1
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1k
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Limit on continuously writing to a log file
I am using Debian running on a BeableBone Black with 4GB of internal flash storage.
My program is continuously writing / appending to a log file that I created with >> every minute, all day ...
- 1,121
2
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1
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1k
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U-boot messages regarding partition switches not understood
I am using a BeagleBone board with the default Debian image flashed to the internal emmc.
I'm trying to understand the U-boot messages below that I get over serial when the device starts, especially ...
- 1,121
1
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0
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110
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Is it possible to access linux/ramdisk code memory from its running system?
I'm working with an embedded Linux device that has to be auditioned by a regulatory agency.
The agency will select a few devices in the field to check if the code running is the same as auditioned.
...
- 113
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1
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3k
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Interpreting /proc/partitions
I'm confused about the partitions size of a flash memory in my embedded linux device:
/ # cat /proc/partitions
major minor #blocks name
240 0 93184 ndda
240 1 85168 ndda1
...
- 113
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2
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4k
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Rootfs versus kernel confusion [closed]
I know that they are two different entities. Rootfs is a file system which describes how to store and access data. The kernel is actual code which executes.
However, isn't the kernel code stored ...
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1
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730
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How to format a rogue flash drive? (GParted tries to touch file system footer beyond actual capacity, and freezes up indefinitely) [closed]
On a limbo-type fake USB or SD card, all sectors starting from a specific position on the drive are unavailable (zeroes only or ones only or unreadable sector response).
A flash drive might indicate ...
- 1,680
1
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1
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352
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Passwordless encryption of flash drive
I am using Ubuntu and I have an encrypted flash drive which synchronizes with a folder on my desktop whenever I plug it into the computer (using rsync and a systemctl service that runs the bash script ...
- 113
1
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0
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642
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Cannot access nand or emmc partition from linux
I have a i.mx6 based board running using buildroot and linux.
This board have two storages nand and emmc. The nand had full rootfs and kernel on itself. I am now booting from SD card.
From the boot ...
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1
answer
145
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Moving an Linux OS image from a 4 GB flash drive to a hard drive
I have a small flash drive (4 GB) that has a stripped down version of Redhat Linux. I'm currently attempting to move this OS from the flash drive to a much bigger hard drive (500 GB) that is bootable. ...
- 121
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1
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341
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Apply incremental patches on ubifs volume
To update a ubifs volume by replacing it with entirely new content, ubiupdatevol from mtd-utils can be used:
ubiupdatevol /dev/ubiX_Y /path/to/ubifs.img
Is there a way to apply patch on ubifs volume ...
- 101
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1
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982
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How can I create a bootable flash drive for Lbuntu and also store temporarily other personal files in the same flash drive?
I have a flash drive, whose information given by sudo fdisk -l is
Device Boot Start End Sectors Size Id Type
/dev/sdb1 1 7864319 7864319 3.8G c W95 FAT32 (LBA)
I would like to ...
- 99k
-2
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1
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117
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Question regarding naming EEPROM [closed]
EEPROM stands for electronically erasable programmable read-only memory.
If it's erasable and programmable then why it's called read-only memory?
Question should suggest that I am new in all these ...
- 179
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1
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982
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f3read - what is the difference between corrupted, changed and overwritten sectors?
I'm using f3 to test hundreds of USB flash memory sticks for errors.
Here's an example output from a faulty drive. First writing test files with f3write:
Free space: 3.74 GB
Creating file 1.h2w ... ...
- 1,725
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953
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UBIFS going into Read only mode
I have a customer unit having UBIFS file system on it. Unit is up and running fine. The unit under goes a test of power cycling (AC mode-Battery mode- AC mode). At some point of time the unit(UBIFS ...
- 749
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1
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2k
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How can I backup Linux kernel image
Board with ARM926EJ CPU, running embedded Linux v2.6.26.5, on NAND Flash device, NAND 32MiB. Linux is on MTD partitions on NAND device.
How can I backup Linux kernel image (SP2Xcybertan_rom_bin) from ...
- 511
1
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0
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220
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Search data stored on memory for particular string
Is it possible to search data stored on memory for particular string?
Example: we want display memory contents corresponding to particular string in code, is possible search for this string and ...
- 1,353