Velutia

An instruction-level accurate MOS 6502 CPU emulator written in C# (.NET 10).

Features

• Supports all 256 documented & undocumented instructions from the 6502 instruction set.
• Passes all of Tom Harte's 6502 Single Step Tests.
• Instruction-level accuracy.
• Implemented as a .NET library which can easily be integrated into a system emulation project.

Usage

To use the emulator, simply download the project and reference Velutia.Cpu.csproj in your project.

Testing

To run the tests, open the Velutia.Cpu.Tests project and run it. NUnit will run 249 instruction tests, and each test will execute the 10,000 single step tests associated with that instruction:

Note

Because seven of the undocumented instructions are inherently unstable, their tests are not run. They include:

• ANE
• LXA
• SHA (Abs, y & Ind, Y)
• SHX
• SHY
• TAS