Remember that this emulator requires Atari ROMs to be present in "/3ds/atari800"! However, Atari allowed the ROMs to be distributed alongside a different emulator, which is now freely available, in 1994. You can download it here - copy over the .ROM files to "/3ds/atari800".

 

Please run DspDump before running atari800!

 

If you're stuck, press L to access the emulator's menu!