Developing

Disk Layout

The control box has 2 disks, an OS disk, and optional DATA disk. The OS disk contains at least 2 partitions, labelled BOOT and VAR. Boxes with a development environment installed also have a DEV partition. The purpose of these is as follows:

• BOOT is not mounted in a running system. It's used by the bootloader to launch either the development or production EM operating system. It contains a bootloader config at "/grub/grub.conf" and any number of software images, such as /em-X.Y.Z which contain the entire production EM system.
• VAR is a run-time data directory. When a production EM system runs, the root directory (/) is read-only, and is loaded from the image file. Any files that need to be editable in the production system are stored here. The VAR partition is mounted at the /var location.
• DEV is the development environment. It may be used in place of a read-only production image.

File Layout

/opt - custom software /opt/em - the EM software /opt/elog - the Elog software (optional) /var - the run-time data directory /var/em - editable EM files, like config. /var/em/data - backup data storage. data recorded is cached here before flushing to /mnt/data, in case the data disk is missing and for a backup. Only a short period of video is stored here at a time due to space constraints. /var/elog - /mnt/data - the data disk mount point, all data recorded is stored here. /etc/em.conf - the EM system config file. links to /var/em/em.conf in order to be writable. /etc/systemd/system - startup scripts, which defined dependencies and processes on boot /tmp/em-state.json - a JSON api that can be read to get the system state from the filesystem any time. Used by the web interface (UI) as well.

Hardware Schematics

https://tools.upverter.com/eda/#tool=schematic,designId=4366e16d02cdfda3

How To Set Up A New Control Box after it's assembled.

• Flash the BIOS.
• Apply BIOS settings.
• Image the disk.
• Test with external sensors and peripherals, and a data disk.
• Set the Screen Resolution.
• Apply configuration settings if needed (include in the image ideally)