I got this working on my Tontec 3.5 Inch Touch Screen. What you will need to do is setup Framebuffer Mirroring using the rpi-fbcp program on github.

After you have setup your screen, and it is displaying, you will need to execute these linux commands to compile and install the Framebuffer Mirroring program:

sudo apt-get install cmake
git clone https://github.com/tasanakorn/rpi-fbcp
cd rpi-fbcp/
mkdir build
cd build/
cmake ..
make
sudo install fbcp /usr/local/bin/fbcp

#now make sure you are cd'ed into the build folder, now run the program:
fbcp &

#now you can run emulation station:
emulationstation

This program basically copies screen frames over from fb0 (hdmi) to fb1 (lcd screen).

Resource:
https://github.com/tasanakorn/rpi-fbcp
https://github.com/notro/fbtft/wiki/Framebuffer-use

Hi Leoman36,

After a reboot I make sure I am in the build directory which contains the compiled fbcp program and should probably be located in rpi-fbcp/build/ on your Pi. After I CD to that directory, I execute the fbcp program again and then EmulationStation. Try the following commands after a reboot:

cd rpi-fbcp/build/
fbcp &
emulationstation