The FunKey S retro-gaming console software contains a set of console emulators, standalone games, applications and utilities using a custom Operating System (OS) that from now on will be referenced as FunKey-OS.
The FunKey-OS is a Linux-based operating system, optimized for the FunKey-S hardware, with a special focus on performance and fast boot time.
The FunKey S introduces a unique feature called Instant Action, which enables automatically saving the running state when closing the console before turning it off, and restoring this state when opening and turning it back on in a matter of seconds.
This feature is only possible because of the optimized fast boot time detailed in the Boot Process section.
The only storage system available in the FunKey S is its integrated MicroSD card. Most of its contents is made available to a host computer when connected over USB.
The MicroSD card format is detailed in the Disk Partition section.
The FunKey-S CPU does not feature a GPU. For this reason, the FunKey-S cannot use a hardware-accelerated OpenGL engine, and adding a software-emulated OpenGL-ES engine is not efficient, given the limited CPU performance.
However, because of the small screen size and the fact that all applications are used in full-screen mode only, there is no need for a full-blown windowing system like X11, which greatly simplifies the video processing as no window overlapping or frame decoration is thus required.
Instead, all graphical computations are performed by the CPU itself, directly into the video frame buffer that will be sent to the screen for display.
The FunKey S has no standard keyboard but features common console-oriented controls in the form of a D-Pad, A/B/X/Y Pad, Menu/On/Off, Fn and Start buttons.