Disabling write protect with a SuzyQable
TIP
This method is only available on CR50 devices.
TIP
This method requires a SuzyQable, a chromeOS debug cable.
Step 1: Enabling Closed Case Debugging (CCD)
- Open VT-2 (
ctrl
+alt
+f2
(right arrow)). - Login as
root
. - Run
gsctool -a -o
. - You will be prompted to press the
PP
(physical presence) button several times. This is a fancy way of saying to press the power button. This process takes several minutes and ends with the messagePP Done!
. - The device will suddenly reboot and exit developer mode. Re-enable developer mode and continue with the instructions.
Step 2: Disable Write Protect
- Open VT-2 (
ctrl
+alt
+f2
(right arrow)). - Login as
root
. - Plug in your cable
- Run
ls /dev/ttyUSB*
to verify your cable is working. This should output 3 items,ttyUSB0
,ttyUSB1
, andttyUSB2
. If you do not see these items, try flipping theusb-c
end upside-down, and try anotherusb-c
port. If there is still no result, confirm your cable was assembled properly. - Run the following commands. This will disable hardware write protect.
echo "wp false" > /dev/ttyUSB0
echo "wp false atboot" > /dev/ttyUSB0
- Run
echo "ccd reset factory" > /dev/ttyUSB0
to be able to unbrick using a suzyqable, if needed. - Run
gsctool -a -I
to verify you have opened all the CCD flags. The current value for all CCD flags should be set to Y/Always. - Verify
crossystem wpsw_cur
returns0
. - Reboot.