ccgx booting and buttons

• When pressing the two top buttons, the CCGX will be reset. This is a pure hardware function.
• When holding the left button of the five-button-central-pad while booting causes MLO on NAND to start u-boot (in NAND) instead of (as it normally does) the linux kernel. It looks for a .src script on either the sdcard or an USB-stick. When found, it executes that script. Typically used for firmware updating and recovery.
• Holding both the left button of the five-button-central-pad, and the top left button, also start u-boot. And then causes u-boot to stop and stay available: it won't start a scr script, or continue normal boot in case no .scr script is found.

So, to get into u-boot, hold the two left buttons, and then momentarily press the top right button.

User instructions to update ccgx firmware using an SD-card or USB stick are here: http://www.victronenergy.com/live/ccgx:firmware_updating

In case you have bricked the device, by putting a broken u-boot on the NAND, there is still a way to force it to . Use a screwdriver to short some pin on the technexxion cpu-board.

Put differently: to work on boot loaders, it is better to use a standard technexxion cpu-board, since that will always check the sdcard.

Normal boot order

MLO -> Linux (yes, u-boot is skipped)

Programming the factory

We receive the boards with a completely empty NAND. The CPU will then look for MLO at a special sector on the sdcard, and start that. And that sdcard is what we provide to our factory.