Nuked-OPL3 DLL Wrapper

This project is a Windows DLL wrapper around NukeyKT's cycle‑accurate OPL3 (YMF262) emulator.
The goal of this fork is to provide a simple and stable C API for applications that need real‑time OPL2/OPL3 FM synthesis, register‑level access, or audio sample generation.

The emulator core is kept mostly unmodified from the original Nuked‑OPL3 project.
Only "fake" timer emulation (for detection) and a lightweight DLL interface and supporting glue code have been added.

Emulators supporting the DLL:

• YAPE - a Commodore 264 family emulator for Windows (http://yape.homeserver.hu/)
• WinTVC - a Videoton TV Computer emulator for Windows (http://gaia.atilia.eu/downloads.html)

Features

• Cycle‑accurate Yamaha YMF262 (OPL3) emulation
• Supports both OPL2 and OPL3 modes
• Real‑time PCM audio generation
• Register‑accurate read/write interface
• Adjustable sample rate and amplitude
• Simple C API suitable for any language that can load a DLL
• Single‑instance design for easy integration

Exported API

void DLL_EXPORT oplCreate(unsigned int model, unsigned int replayFreq);
void DLL_EXPORT oplDestroy();
void DLL_EXPORT oplSetSampleRate(unsigned int sampleRate_);
void DLL_EXPORT oplSetModel(unsigned int model);
void DLL_EXPORT oplReset();
void DLL_EXPORT oplPause();
void DLL_EXPORT oplWriteReg(unsigned int reg, unsigned char value);
unsigned char DLL_EXPORT oplReadReg(unsigned int reg);
void DLL_EXPORT oplCalcSamples(short* buf, long count);
short DLL_EXPORT oplCalcSample();
void DLL_EXPORT oplSetAmp(unsigned int amp);
const DLL_EXPORT char* oplGetLibVersion();

API Description

Initialization

oplCreate(unsigned int model, unsigned int replayFreq)

Creates and initializes the OPL emulator instance.

• model = 0 → OPL2 mode
• model = 1 → OPL3 mode
• replayFreq = internal update frequency (typically 49716 Hz)

oplDestroy()

Destroys the emulator instance and frees resources.

Configuration

oplSetSampleRate(unsigned int sampleRate_)

Sets the output PCM sample rate.

oplSetModel(unsigned int model)

Switches between OPL2 and OPL3 modes.

oplSetAmp(unsigned int amp)

Sets output amplitude scaling.

oplReset()

Resets the chip to its power‑on state.

oplPause()

Pauses audio generation without destroying state.

Register Access

oplWriteReg(unsigned int reg, unsigned char value)

Writes a value to an OPL register.

unsigned char oplReadReg(unsigned int reg)

Reads back the last written value of an OPL register.

Audio Generation

oplCalcSamples(short* buf, long count)

Generates count samples of 16‑bit signed PCM audio into buf.

short oplCalcSample()

Generates and returns a single PCM sample.

Version

const char* oplGetLibVersion()

Returns a static version string for the DLL.

Building

The DLL can be built using:

• Microsoft Visual Studio
• MinGW‑w64
• Clang‑CL

No external dependencies are required.

License

This fork follows the original Nuked‑OPL3 license (LGPL). Please refer to the upstream project for licensing details.

Upstream Project

Nuked‑OPL3 by NukeyKT
https://github.com/nukeykt/Nuked-OPL3