SD Card
Contents
Formatting SD Card
Use fdisk to format the SD card.
Locating SD Card on System
The mount command can be used to locate the SD card device, once it has been connected to the host computer. In the example below, an SD card has been connected on /dev/sdb1 and mounted at /media/user/UNTITLED.
user@ubuntu:~$ mount /dev/sda1 on / type ext4 (rw,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) none on /sys/fs/cgroup type tmpfs (rw) none on /sys/fs/fuse/connections type fusectl (rw) none on /sys/kernel/debug type debugfs (rw) none on /sys/kernel/security type securityfs (rw) udev on /dev type devtmpfs (rw,mode=0755) devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=0620) tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=0755) none on /run/lock type tmpfs (rw,noexec,nosuid,nodev,size=5242880) none on /run/shm type tmpfs (rw,nosuid,nodev) none on /run/user type tmpfs (rw,noexec,nosuid,nodev,size=104857600,mode=0755) none on /sys/fs/pstore type pstore (rw) binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,noexec,nosuid,nodev) systemd on /sys/fs/cgroup/systemd type cgroup (rw,noexec,nosuid,nodev,none,name=systemd) gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,user=russellbush) /dev/sdb1 on /media/user/UNTITLED type vfat (rw,nosuid,nodev,uid=1000,gid=1000,shortname=mixed,dmask=0077, utf8=1,showexec,flush,uhelper=udisks2)
Partitioning the SD Card (fdisk)
Before partitioning the SD card, any partitions that have been mounted on the system must be unmounted. This can be done using the umount command.
umount /dev/sdb1
Once the SD card has been located, we can partition it for the Linux system (BOOT partition) and root filesystem (ROOTFS partition) using fdisk. fdisk must be run with root permissions (sudo) using the disk parent as the argument (do not use the parition number in the argument).
sudo fdisk /dev/sdb
From within the fdisk interface, we can view the parition table at any time using the "p" command. In this example, an 8GB SD card with a single FAT32 partition is being used and will be re-partitioned for snickerdoodle.
Command (m for help): p Disk /dev/sdb: 7969 MB, 7969177600 bytes 255 heads, 63 sectors/track, 968 cylinders, total 15564800 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdb1 8192 15564799 7778304 b W95 FAT32