Scroll down on the same page and select * Save Core Remap File. Go to Quick Menu -> Input Options and set the User 1 Device Type and User 2 Device Type to MD Joypad 6 Button. Launch a Megadrive game and go into the RetroArch menu (default mapping: Select + X). You can save a Core Remap File which reloads every time the emulator is launched. There are two ways to achieve this, most people will want to use Option 1: Option 1 - RetroArch Menu

Lr-genesis-plus-gx and lr-picodrive utilise RetroArch configurationsДЄdd custom retroarch controls to the retroarch.cfg file in /opt/retropie/configs/megadrive/retroarch.cfgДЇor more information on custom RetroArch controls see: RetroArch Configuration Configuring a 6 button controllerДЇirst you need to tell retroarch to use 6 buttons, because the default is to use 3. There are two methods for configuring controls - one way for both lr-genesis-plus-gx and lr-picodrive, and another way for DGen. Or /home/pi/RetroPie/roms/genesis (symlinked to megadrive folder to remove confusion) Place your ROMS in either /home/pi/RetroPie/roms/megadrive DGen has the worst performance and can be tedious to configure the controls for. lr-picodrive is more suited for use on the Pi 0/Pi 1 due to its speed. Lr-genesis-plus-gx is best for the Pi 3/Pi 2 due to its accuracy.

opt/retropie/configs/megadrive/retroarch.cfgД®mulators: lr-genesis-plus-gx, lr-picodrive, DGen

This console, known as the Mega Drive everywhere except in the USA where it was renamed Genesis, was released by Sega in 1988

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