https://gdemu.wordpress.com/operation/gdemu-operation/
INI file:
A simple text INI file can be put into root folder of the SD card to modify some of the GDEMU default settings. The file should be named GDEMU.ini.
IMPORTANT: Settings are read during SD card detection phase, so changing the card will result in GDEMU re-reading them again. This way it is possible to have different settings per card. If no INI file is found, the previous values will remain in effect.
Available settings:
[*] open_time = N
Where N is natural number in range 150 to 5000, expressed in miliseconds. Defines how long GDEMU will idle with “lid open” status presented to the console after image change. Default is 500ms.
[*] detect_time = N
Where N is natural number in range 150 to 5000, expressed in miliseconds. Defines how long GDEMU will idle with “busy” status presented to the console after image change. Default is 250ms.
[*] image_tests = B
Where B is 0 (disabled) or 1 (enabled). If disabled, image integrity tests will be relaxed to allow oversized media. Note that correct operation is not guaranteed with such images. Default is enabled.
[*] high_speed = B
Where B is 0 (disabled) or 1 (enabled). If enabled, GDEMU will transfer data from SD card in high speed mode . Note that this is an experimental option and might not work properly. Default is disabled.
[*] reset_goto = N
Where N is natural number in range 0 to 9999. If enabled (N > 0), GDEMU will switch to image number N when it detects system reset. Default is disabled.