To install RetroPie on to a clean SD card you will need to download the lastest image (make sure you download the right one for your version of Raspberry Pi) from the RetroPie website and extract the .GZ file. You will be left with a .IMG file which you will need to write to the SD Card using Win32DiskImager on Windows machine.
After the image has been written to your SD card you will need to insert the card in to your Raspberry Pi. Make sure you plug in the HDMI, keyboard and either Ethernet cable or a WIFI dongle. I am also using the retropie GPIO adapter with an original controller. I will be using a WIFI dongle for this tutorial. Your Pi will take a couple of minutes to boot as this is the first boot from a new image. If you are using a USB controller it will have detected a controller.
As RetroPie didn’t detect any controllers you will need to press F4 on your keyboard and load the raspberry config using the command
There is a couple of things you will need to do within this config. First you will need to “1 Expand Filesystem” this will expand the size of the available memory on your chosen SD card.
The next thing you will want to do is to select “9 Advance Options” and then “4 SSH” and enable SSH. By enabling this you will be able to connect to the terminal from a different device like a computer or tablet.
This part is optional now, I have overclocked my Raspberry Pi to medium 900MHZ to help it run the emulators nice and smoothly. After you have done this you will want to exit and reboot you RPi.
Now the Raspberry Pi config has been completed, its time to go through the RetroPie config.
cd RetroPie-Setup sudo ./retropie_setup.sh
If you are using a WIFI dongle to connect the internet you will need to select “3 Setup / Configuration” and scroll down to “326 Configure WIFI”. After click “1 Connect to WIFI networks” this should bring up all available WIFI networks, enter your WIFI password and now you should be connect to the internet.
As im using the RetroPie GPIO adapter you will need to activate “322 SNESDev” from within the Setup page. First, select the version of the adapter you have, I have version 1.4 so I select “5 switch to adapter version 1.x”. After the correct software drivers have downloaded, you will need to select “3 Enable SNESDev on boot (polling only pads). After this has been completed you will want to reboot your Raspberry Pi.
Now your RetroPie system has been setup, it should detect your original controllers. You just need to hold a button down on your controller to get the setup to begin. Follow the on screen controls and map your controller to the correct commands. Now all that is left to do is to upload your ROMS.