Nebula Files and Static Values
During the installation of a new JAR device Nebula creates a directory named Nebula in your home directory. The paths and filenames are initialized in Startup if you want to change them. A reference to to all files is held in class Static_Values. Inside the Nebula directory, JAR devices create directories to match the ones commonly used by Android. They are Audio, Documents, Downloads, Photos and Videos. The root file path for Android is to packagePath/files/Nebula. Both JAR and APK devices create a Nebula/UserData directory. Each of these created directories is for the sole purpose of transferring files between devices when using the demo commands SendFile and Get File. The demo commands do not allow file transfer to a directory name other than the one they originate from.
The essential directory for every Nebula device is Nebula/NebulaDataFiles. Inside the NebulaDataFiles directory are 3 files:
BIN Device Files
Arduino based WiFi devices use SPI Flash Filing System (SPIFFS). It’s used for embedded microprocessor systems with little RAM. Nebula configures a 4MB WiFi device to use 1MB for SPIFFS and 3MB for code and data. A SPIFFS file system is flat, meaning it does not use directories. More information can be found here. Nebula files on SPIFFS are:
- The size of a device file is typically less than 70 bytes but can be around 200 bytes for a mobile device with a long email address.
Essential Operating System elements
Essential Nebula files initialized in Startup
Local device essentials
- Command class name must be included in the nativeCmds or demoCmds array to make it usable.
- Commands with show = “true” are shown in the user command selection box in the order they are listed here.
- Following the above is where all command and command-success IDs are listed. See command_files.Static_Values for default values and details.
- The last section of Static_Values is for convenience in getting Device elements.