Find SD Device

From Technologic Systems Manuals

For imaging the SD card we recommend using a Linux or similar operating system that allows you to access a block device using dd. We do not support rewriting the SD card from Windows.

If you are reprogramming the SD card from your workstation you will also need to determine the SD card device. Once you have connected the SD card to your workstation you can usually find the correct block device in the output of "dmesg". For example:

 [  309.498834] sd 8:0:0:0: [sdb] 3862528 512-byte logical blocks: (1.97 GB/1.84 GiB)
 [  309.519814] sd 8:0:0:0: [sdb] Write Protect is off
 [  309.519818] sd 8:0:0:0: [sdb] Mode Sense: 03 00 00 00
 [  309.519819] sd 8:0:0:0: [sdb] Assuming drive cache: write through
 [  309.536025] sd 8:0:0:0: [sdb] Assuming drive cache: write through
 [  309.536029]  sdb: sdb1 sdb2 sdb3
 [  309.559672] sd 8:0:0:0: [sdb] Assuming drive cache: write through
 [  309.559676] sd 8:0:0:0: [sdb] Attached SCSI removable disk

On this system my SD card block device is /dev/sdb, but your system will likely be different. The block devices are allocated in order by the letter so the next USB drive connected would be /dev/sdc. On some newer kernels you will see '/dev/mmcblk0' as the block device and '/dev/mmcblk0p1' for the first partition. For these examples I will use the '/dev/mmcblk0' format.

WARNING: Many distributions will name your hard drive something like /dev/sda or /dev/hda which will have the same naming scheme as an SD card or a USB drive. Make sure you are aware which device is which before writing the disk. Technologic Systems is not responsible for any data lost/destroyed because of improper command execution.