There are 4 different ways to erase all data on the onboard eMMC storage:
- Keys Mode (Side-Buttons)
- Serial Mode
- Interrupt Mode
- CLI Mode
All ROMs we have released support eMMC erasure. Please follow the steps below to erase the data on the eMMC:
- Power on VIM.
- Long press
Functionbuttons simultaneously, without releasing them.
- Short press the ‘Reset’ key and release.
- After the operations above, the system will begin to erase automatically; it will take about 10 seconds to finish.
- Your connected display/monitor will display a black screen when the erasure process is complete.
- Refer to this guide to setup the Serial Tool for your VIM.
- Once again, ensure you’ve done the correct connections and setup.
- Hit any keys at the moment of bootup to stop autoboot. This step will make your VIM enter into u-boot mode.
store init 3on the terminal of u-boot, and wait for the erasure process to complete.
rebootor press the
- Use the following as a reference:
Vim# store init 3
emmc/sd response timeout, cmd8, status=0x1ff2800
emmc/sd response timeout, cmd55, status=0x1ff2800
[mmc_startup] mmc refix success
[mmc_init] mmc init success
switch to partitions #0, OK
mmc1(part 0) is current device
Device: SDIO Port C
Manufacturer ID: 15
Tran Speed: 52000000
Rd Block Len: 512
MMC version 5.0
High Capacity: Yes
Capacity: 7.3 GiB
mmc clock: 40000000
Bus Width: 8-bit DDR
[store]amlmmc erase 1emmckey_is_protected : protect
start = 0,end = 57343
Caution! Your devices Erase group is 0x400
The erase range would be change to 0x36000~0xe8ffff
start = 221184,end = 15269886
If the erasure process completed successfully, the terminal should look like this when you power on your device:
This approach is suitable for all products that use the Amlogic SoC:
- Carry out normal upgrading via USB-C Cable or TF Card.
- Manually interrupt the upgrading process (forcefully disconnect after 15% is recommended). For example, unplug the USB-C cable or the TF card.
- Power on your VIM again, and you’ll find that all the data on the eMMC has been erased.
This approach is suitable for a VIM that has Linux installed:
- Power on and boot up.
- Open a terminal, and run
ddto fill your bootloader partition with zeros:
root@Khadas:~# dd if=/dev/zero of=/dev/bootloader
dd: writing to '/dev/bootloader': No space left on device
8193+0 records in
8192+0 records out
4194304 bytes (4.2 MB, 4.0 MiB) copied, 1.1226 s, 3.7 MB/s