11
ROM-5420 User Manual
Chapter 3
S
oftware
Functionality
Step 3: Write and check
#echo -n "0123456789ABCDEF" | dd of=/dev/sdb bs=1024 count=1
seek=25118
0+1 records in
0+1 records out
#hexdump -C /dev/sdb -s 25720832 -n 16
01887800 30 31 32 33 34 35 36 37 38 39 41 42 43 44 45 46 |0123456789ABCDEF|
3.1.4
SD Test
Step 1: When booting from eMMC, you would see only below directories:
#ls /dev/mmcblk*
/dev/mmcblk0 /dev/mmcblk0boot0 /dev/mmcblk0boot1 /dev/mmcblk0p1
Step 2: Insert SD card to SD card slot and check your device again. You should be
able to see more directories. /dev/mmcblk1 is the SD card storage.
#ls /dev/mmcblk*
/dev/mmcblk0 /dev/mmcblk0boot1 /dev/mmcblk1 /dev/mmcblk1p2
/dev/mmcblk0boot0 /dev/mmcblk0p1 /dev/mmcblk1p1
Step 3: Erase and check
#dd if=/dev/zero of=/dev/mmcblk1 bs=1024 count=1 seek=25118
1+0 records in
1+0 records out
#hexdump -C /dev/mmcblk0 -s 25720832 -n 16
01887800 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
Step 4: Write and check
#echo -n "0123456789ABCDEF" | dd of=/dev/mmcblk1 bs=1024 count=1
seek=25118
0+1 records in
0+1 records out
#hexdump -C /dev/mmcblk0 -s 25720832 -n 16
01887800 30 31 32 33 34 35 36 37 38 39 41 42 43 44 45 46 |0123456789ABCDEF|
Note!
This operation may damage the data stored in USB flash disk. Please
make sure there is no critical data in the USB flash disk being used for
this test.