The service button is handy as it lets you set Lives per credit, game difficulty etc for each game.
Simple mod to MVS Simulator for Dingoo A320.
This map L and R triggers to:
PAD_LTRIGGER - ServiceCoin
PAD_RTRIGGER - TestSwitch
In this case you can access with R trigger to NeoGeo machine
settings and adjust hard and soft dip switches.
HOW TO INSTALL:
Copy MVS.SIM to dingoo GAME folder.
Empty your \GAME\MVS\config folder (delete all .ini files). Dont worry they will be recreated.
Reset your dingoo.
Thats all.
HOW TO USE:
After load game press R trigger.
This will bring machine settngs to you. A & B buttons select options. X back to previous menu.
Soft dip is game settings (i.e. enable red blood on metal slug games).
Enjoy.
You can get the download HERE or HERE