[???]

 Leprechaun 

 Main CPU

 0000-03ff RAM
 8000-ffff ROM

 2000-200f, 2800-280f and 3000-300f might be some kind of programmable I/O
 controller. I'm not knowledgable enough about them to be able to tell for sure.
 I based the observation of the locations being written/read. They seem to
 follow a similar pattern across all 3 areas. Anyone with schematics?

 I/O Read

 2000 Video RAM Read Back
 200d ???
 3002-3003 ???
 2801 Input Port Read

 I/O Write

 2000 Graphics Command Write
 2001 Graphics Data Write
 2002-2003 ???
 200c-200e ???
 2800 Input Port Select
 2802-2803 ???
 280c ???
 3001 Sound Command Write
 3002-3003 ???
 300c ???


 Sound CPU

 0000-01ff RAM
 f000-ffff ROM

 I/O Read

 0800 Sound Command Read
 0804-0805 ???
 080c ???
 a001 ???

 I/O Write

 0801-0803 ???
 0806 ???
 081e ???
 a000 AY8910 Control Port
 a002 AY8910 Write Port

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