# OEM Image Setup ## **Linux** **Prerequisites：**Android-tools：\*\* * Download and unzip following files: * simg2img]\() * img2simg]\() * Remote Unit: [oem\_ru\_base.img](https://herelinkfw.cubepilot.org/tools/oem_ru_base.img) * Air Unit: [oem\_au\_base.img](https://herelinkfw.cubepilot.org/tools/oem_au_base.img) * Ensure that you select the base image depending upon which unit you are modifying. * Download and extract zips into same directory. * Now to generate ext4fs image from the sparse image (.img) downloaded above do `./simg2img_mac oem_au_base.img raw_oem_au_base.img` * Create a mount point directory using `mkdir oem` * Mount the image using `mount raw_oem_au_base.img oem` * Now you should be able to modify files inside the mount directory. * You need to use `sudo` to be able to do any writes the files inside the mount point. * Once you have made your changes, you need to unmount your drive using command `sudo umount oem` * Afterwards convert the ext4fs image back to android sparse image using command `./img2simg raw_oem_au_base.img oem_au.img` * Now you may flash this image into Herelink Air Unit, by putting it under bootloader using command `adb reboot bootloader` * And finally to flash to image run command `fastboot flash oem oem_au.img` * Check example below for a sample modification. ## **MacOS** **Prerequisites：**Homebrew：\*\* * Setup osxfuse in your system using `brew cask install osxfuse`, this will require rebooting your system proceed and do that。 * Follow the steps [here](https://github.com/alperakcan/fuse-ext2#macos) to install fuse-ext2. This will allow you to mount ext4fs we will be generating. * Download and unzip following files: * simg2img： * img2simg： * Remote Unit： * Air Unit： * Ensure that you select the base image depending upon which unit you are modifying. * Download and extract zips into same directory. * Now to generate ext4fs image from the sparse image (.img) downloaded above do`./simg2img_mac oem_au_base.img raw_oem_au_base.img` * Create a mount point directory using`mkdir oem` * Mount the image using * `fuse-ext2 raw_oem_au_base.img oem -o rw+` * Now you should be able to modify files inside the mount directory. * You need to use `sudo` to be able to do any writes the files inside the mount point. * Once you have made your changes, you need to unmount your drive using command`sudo umount oem` * Afterwards convert the ext4fs image back to android sparse image using command`./img2simg raw_oem_au_base.img oem_au.img` * Now you may flash this image into Herelink Air Unit, by putting it under bootloader using command `adb reboot bootloader` * And finally to flash to image run command：`fastboot flash oem oem_au.img` **Example：** * In the following example we change the system\_id used by herelink air unit for board specific messages. * Most config files are located in you unit at `/system/etc`in the following example we will pull config using command `adb pull /system/etc/system-control.telepathy-air.conf` * Once pulled the file will contain information like bellow: `# module on/offboard_control_enabled = trued2d_tracker_enabled = truecamera_control_enabled = true# board controlboard_system_id = 42# camera controlvideo_stream_ip_address = 192.168.0.10camera_system_id = 42support_multiple_camera = truesupport_camera_capture = false` * You can change the value of `board_system_id` and `camera_system_id` fields as per your requirement in your favourite editor. * Once done save this file and exit editor. * Create a folder inside oem image called `etc` using command `sudo mkdir oem/etc` * Copy file using command `sudo cp system-control.telepathy-air.conf oem/etc/` * Continue to unmount the image and flashing into the unit as described in above steps. ### **Example App Change** * In the following example we override the installed QGroundcontrol App. * A new OEM app can be installed under /oem/app//.apk * For installing your custom version of QGroundcontrol, ensure that you started with as your base. * After building the project, create a folder `QgroundControl` * Copy .apk file `cp -r build-qgroundcontrol-Android_for_armeabi_v7a_Clang_Qt_5_11_0_for_Android_armv72_fd6ff4-Debug/android-build/build/outputs/apk/android-build-debug.apk QGroundControl/QGroundControl.apk` * Also create a lib directory `QGroundControl/lib` * Copy libraries `cp -r build-qgroundcontrol-Android_for_armeabi_v7a_Clang_Qt_5_11_0_for_Android_armv72_fd6ff4-Debug/android-build/libs/armeabi-v7a/ QGroundControl/lib/arm/` * Finally move QgroundControl directory to oem image `sudo cp -r QGroundControl oem/app/QGroundControl` * Do ensure you have already created app directory inside oem image if not already done `sudo mkdir oem/app` * Continue to unmount the image and flashing into the unit as described in above steps. ### **Extra OEM Files：** * On boot several files are setup for use, and you can override these files * These files can exist in (searched in this order) `/data/oem/etc - user default - wiped on factory reset/oem/etc - oem default/system/etc - system default` * files that can be overridden (optimus is the internal GCS name, telepathy-air is the air unit (ro.product.device)) `lampsignal-telepathy-air.jsonrc_service_config_optimus.inimavlink-router.optimus.confsystem-control.optimus.conf`[PreviousInstalling a custom app](https://docs.cubepilot.org/user-guides/herelink/herelink-user-guides/installing-a-custom-app)[NextGenerate a bug report](https://docs.cubepilot.org/user-guides/herelink/herelink-user-guides/generate-a-bug-report)