掌機 - Anbernic RG28XX - Extract environment

參考資訊：
https://knulli.org/guides/h700-firmware-extract/
https://github.com/anestisb/android-unpackbootimg

步驟如下：

$ cd 
$ wget https://github.com/steward-fu/website/releases/download/rg28xx/RG28XX-V1.0.4-EN16GB-240511.7z
$ 7za x RG28XX-V1.0.4-EN16GB-240511.7z
$ sudo fdisk -l RG28XX-V1.0.4-EN16GB-240511.IMG 
    Disk RG28XX-V1.0.4-EN16GB-240511.IMG: 14.48 GiB, 15552479232 bytes, 30375936 sectors
    Units: sectors of 1 * 512 = 512 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disklabel type: gpt
    Disk identifier: AB6F3888-569A-4926-9668-80941DCB40BC

    Device                              Start      End  Sectors  Size Type
    RG28XX-V1.0.4-EN16GB-240511.IMG1    73728  8880127  8806400  4.2G Microsoft basic data
    RG28XX-V1.0.4-EN16GB-240511.IMG2  8880128  8945663    65536   32M Microsoft basic data
    RG28XX-V1.0.4-EN16GB-240511.IMG3  8945664  8978431    32768   16M Microsoft basic data
    RG28XX-V1.0.4-EN16GB-240511.IMG4  8978432  9109503   131072   64M Microsoft basic data
    RG28XX-V1.0.4-EN16GB-240511.IMG5  9109504 25886719 16777216    8G Microsoft basic data
    RG28XX-V1.0.4-EN16GB-240511.IMG6 25886720 30373887  4487168  2.1G Microsoft basic data

$ dd if=RG28XX-V1.0.4-EN16GB-240511.IMG of=env.img bs=512 skip=8945664 count=32768
$ strings env.img > env.txt
$ cat env.txt | head
    earlyprintk=sunxi-uart,0x05000000
    initcall_debug=0
    console=ttyS0,115200
    nand_root=/dev/nand0p4
    mmc_root=/dev/mmcblk0p5
    init=/init
    loglevel=4
    selinux=0
    cma=64M
    mac=

$ mkenvimage -s 0x1000000 -o env.img env.txt