In Emulationstation system settings you find an overclock setting and undervolt options. The overlock option enables 2 GHz operation. While there are 3 levels of undervolting, where L1 is the least undervolt and L3 is the most undervolt. Undervolting can help performance in higher end emulators such as PPSSPP and Yabasanshiro standalone, due to less thermal throttling. As well as less battery drain on lower end emulators.
Obviously it can't be guaranteed that all specimens can undervolt and hence you may end up with a non-booting or unstable system. If this is occurs, the undervolting can be reversed by:
Inserting the OS SD card into a PC.
Open ROCKNIX partition, and go to the extlinux folder.
Open extlinux.conf text file.
Completely remove the line that starts with FDTOVERLAYS.
By default ROCKNIX will detect your controller and configure RetroArch hotkeys automatically. This is controlled by the "AUTOCONFIGURE RETROARCH HOTKEYS" option in the Settings > Controller & Bluetooth menu. While the option is enabled, RetroArch hotkeys will be overwritten by the above defaults each time RetroArch is launched. If this behavior is not desired that option can be disabled and your user-defined RetroArch hotkeys will be used instead.
By default ROCKNIX will expand the configuration file according to the first controller mednafen finds. This only happens when the config file doesn't exist (meaning the first time or if you manually delete it). After the initial expansion you are free to customize the controls.
Z and L button assignment can be changed directly in EmulationStation
Highlight the game and press X(NORTH)
Select ADVANCED GAME OPTIONS
Set EMULATOR to MUPEN64PLUSSA
Then change INPUT ONFIGURATION
Default: L1 = L, L2 = Z
Z & L SWAP: L1 = Z, L2 = L
You can also create your own custom controller configuration and add it to /storage/.configs/game/configs/mupen64plussa. Then update INPUT CONFIGURATION to CUSTOM following the same steps as above.
To add/change mapping you can edit /storage/.config/game/configs/hypseus/hypinput.ini under [KEYBOARD] section by changing third number for a function from 0 (disabled) to a corresponding joystick value. You can identify joystick values by running jstest /dev/input/js0 over ssh.
For example the following would assign quit to L1 and pause to R1
Press L1 + START + SELECT while in EmulationStation to swtich between Screen and HDMI output.
While this should work; it doesn't always result in the correct resolution. The best way to get consistent results is to turn off the device, plug in an HDMI cable and reboot.
"Why doesn't hot-plugging just work?"... Hot-plug HDMI switching is a fairly complex action to accomplish and not something we have implemented on any device. If you are a developer and interested in helping to build this functionality please start here: Contribute