EPSM

NES Expansion Port Sound Module (Earlier: Expansion Port Sound Generator)

An expansion sound card for the Nintendo Entertainment System

It uses an Yamaha YMF288 Soundchip that gives a lot of new audio capabilities to the NES.

Features of YMF288:

• 3 Pulse Channels with Envelope and Noise
• 6 4OP FM Channels with hard panning stereo.
• 6 Rythm channels featuring 6 different ADPCM Drum Recordings with Hard Panning Stereo support
• 2 Timed IRQ's

Added features of the EPSM

• Forwards expansion audio from supported gamecarts
  • Original Famicom expansion audio games with compatible adapter
  • PowerPak
  • EverDrive N8
  • EverDrive N8 Pro
  • Other carts using EXP2, EXP6 or EXP9 to output audio
• Alternative 3.5mm jack for Stereo output
  • EPSM Audio forwarding to the NES RCA/RF outputs are disabled when the 3.5mm jack is plugged in
  • NES Audio and Cart Expansion audio plays as Dual Mono on the 3.5mm jack.

Tools

• Mesen-X: Supports playback of EPSM using any mapper.
• FamiStudio: Allows for music creation for the EPSM and has both ROM and NSF export options.

Usage

• Addressing
• Addressing Fiskbit's Fallback Handler
• NESDev wiki
• N8 Pro Mappers with EPSM Addressing