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###################
AmberELEC internals
###################
`AmberELEC`_ (former 351ELEC) is a fork of `EmuELEC`_, which is a fork of `CoreELEC`_, which is a fork of `LibreELEC`_, which is a fork of `OpenELEC`_). Knowing this inheritance scheme may help you find some lost knowledge and understand reasoning behind some decisions.
.. _AmberELEC: https://github.com/AmberELEC/AmberELEC
.. _EmuELEC: https://github.com/EmuELEC/EmuELEC
.. _CoreELEC: https://github.com/CoreELEC/CoreELEC
.. _LibreELEC: https://github.com/LibreELEC/LibreELEC.tv
.. _OpenELEC: https://github.com/OpenELEC/OpenELEC.tv
How the disk image file is constructed
======================================
The image is built by ``/scripts/mkimage`` script.
The final image has size of 2097 MiB and consists of the following parts:
* 16 MiB - A padding, purpose is unclear. It is defined by ``SYSTEM_PART_START`` variable, measured in sectors, 1 sector = 512 bytes. The ``SYSTEM_PART_START`` variable is defined in the ``/projects/Rockchip/options`` file.
* 2 GiB - System storage partition, a FAT file system, containing the bootloader, the kernel, device tree blobs and the system - a squasfs file of rootfs.
* 32 MiB - Games storage partition, an ext4 file system, to be expanded at first boot to fill out all available memory on the microSD card.
* 1 MiB - Some GPT padding, purpose is unclear.
Tools used in the script:
* ``dd`` is used to create the disk image file.
* ``parted`` is used to crate partitions on the file like if it was a disk.
* ``sync`` is used to fully commit changes made to the file.
* ``mformat`` is used to create boot sector, format the first partition in FAT system and create the root directory on the partition.
* ``mcopy`` is used to copy files into the first partition's file system.
* ``mmd`` is used to create directories inside the first partition's file system.
* ``pigz`` is used to compress the image file
Where the tools are coming from:
* ``dd`` and ``sync`` are from ``/packages/tools/sysutils/coreutils`` package.
* ``pigz`` is from ``/packages/compress/pigz`` package.
* ``mformat``, ``mcopy`` and ``mmd`` are from ``/packages/tools/mtools`` package.
* ``parted`` is from ``/packages/tools/sysutils/parted`` package.
How the system is loaded
========================
The ``init`` script, that ends up in the ``initramfs`` CPIO image, is copied from ``/packages/sysutils/busybox/scripts/init`` file.
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