This is a set of functional tests for the 6502/65C02 type processors. The 6502_functional_test.a65 is an assembler sourcecode to test all valid opcodes and addressing modes of the original NMOS 6502 cpu. The 65C02_extended_opcodes_test.a65c tests all additional opcodes of the 65C02 processor including undefined opcodes. The 6502_interrupt_test.a65 is a simple test to check the interrupt system of both processors. A feedback register is required to inject IRQ and NMI requests. Detailed information about how to configure, assemble and run the tests is included in each source file. The tests have primarily been written to test my own ATMega16 6502 emulator project. You can find it here: http://2m5.de/6502_Emu/index.htm A discussion about the tests can be found here: http://forum.6502.org/viewtopic.php?f=2&t=2241 Good luck debugging your emulator, simulator, fpga core, discrete logic implementation or whatever you have!