Developer and Recovery mode
Table 26. Developer and Recovery mode
Developer Mode Recovery Mode
● Used to boot without verification.
● Can be turned on using key combination during boot.
● Stateful partition is wiped during transitions.
● Used in the factory to boot test image.
● Enables you to reinstall the ChromeOS from a USB drive or
SD card.
● Recovery mode is entered if verified boot fails.
● A user can force recovery mode using a key combination
during boot.
Coreboot and U-boot Custom Firmware
Coreboot (x86 only)
● Memory and chipset initialization
● Open-source, except for MRC binary from Intel.
U-Boot
● Performs verified boot
● Handles recovery and Developer Mode
● Open source code
Normal boot is very fast, as it takes less than one second to start loading kernel. Chromebook does not boot other operating
systems such as Windows or operating system X.
Chrome vs Chromium operating system
Table 27. Difference between Chromium and Chrome OS
Difference between Chromium and ChromeOS
Chromium operating system ChromeOS
● Is an open source project: http://www.chromium.org/
chromium-os
● Runs on regular computers and Chrome devices
● Is based on Chromium operating system
● Only runs on the Chrome devices with required hardware
features (TPM, RO firmware, recovery button, developer
switch).
● Includes additional licensed features such as the Netflix
plug-in, video codecs, and fonts
84 Software