Activating the Bootloader Command Line
The bootloader is configured to automatically boot into the Linux operating system. This feature is aptly called autoboot.
However, autoboot can be stopped so the device remains in the bootloader and opens the bootloader command line. This gives the user access to low level system tools to change settings, flash new firwmare, and more.
Access to the Omega's serial command line is required to use the bootloader.
How to Activate the Bootloader Command Line
By default, the reset button (connected to the FW_RST/GPIO38 pin) controls the autoboot behaviour. If the reset is asserted, autoboot will be stopped.
To stop autoboot:
Connect to the Omega2 command line through serial. Then power on the device and press the SW Reset button at the same time.
The Reset button on the Omega2 Eval Boards and Omega2 Docks is connected to the active-high FW_RST/GPIO38 pin. Pressing the reset button sends a digital-high signal to the FW_RST/GPIO38 pin.
Autoboot will be disabled and the bootloader command line will be visible in the serial command line output.
What if it didn't work?
So you pressed the reset button/held GPIO38 high while powering on the device but you didn't get to the bootloader command line?
That's ok, just power off the device and try again.
How to use the Bootloader Command line
The bootloader prompt offers low level access to the hardware, making it a powerful tool.
Some basics:
- Run the
boot
command to boot into the Linux operating system - Run the
reset
command to reboot the device
To learn more about the bootloader prompt:
- Try running the
help
command to see the available utilities - See the u-boot documentation on the command line and the available utilities
Other things you can do with the bootloader: