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Bits / 2019 / Silver Medal Finish and release 6502 simulator


I started learning 6502 assembly language at the end of 2018, and to get a better understanding of how it works I started building a 6502 simulator using BlitzMax.

There are already hundreds of simulators available, but creating my own helped me to memorize opcodes.

The 6502 chip is well documented and has a solid community. 6502.org in particular has an amazing amount of information, and there’s an entire forum dedicated to building simulators.

There are a total of 56 instructions, but each one has several different modes so there are around 150 different opcodes to implement. For example, ADC (add with carry) has 8 different modes so requires 8 opcodes in the simulator.


Bronze Medal Implement all opcodes
Silver Medal Release the simulator + source
Gold Medal Pass a test suite