The latest update to the vrEmu6502 emulation library now includes (optional) support for all of the unofficial 6502/6510 opcodes.

Use CPU_6502U when creating the new VrEmu6502 instance.

6502/65C02 emulator written in standard C99 with no external dependencies.

Includes:

• Support for standard 6502/6510, 65C02, WDC65C02 and R65C02.
• Supports all unofficial ("illegal") 6502/6510 opcodes (Use model value CPU_6502U).
• Correct handling of Decimal mode.
• Accurate instruction timing.
• All WDC and Rockwell-specific 65C02 instructions.
• User-supplied I/O callbacks.
• IRQ and NMI signals.
• Multiple CPU instances.
• Instruction disassembler.
• Test runner.

Check it out here: https://github.com/visrealm/vrEmu6502