Source: https://www.masswerk.at/nowgobang/2021/6502-illegal-opcodes

Every 6502 enthusiast with some assembly know how under her belt knows, there are secret 6502 opcodes. Some of them are useful, others are not. Some even show unstable behaviour. Did the creators of this extraordinary CPU, which is still in production 40+ years in, wanted to send us a hidden message?

Norbert Landsteiner of mass:werk took a closer look. Much closer. What Norbert reveals in front of us, is not only interesting for 6502 enthusiasts.

It is a lesson on microcode organization. And an excellent one!

And since I do not want to spoil you, I just say: 3-3-2 ... no, that is not 4, 8, 15, 16, 23, 42 🛩

Source: https://www.thebyteattic.com/p/cerberus-2080.html

Source: https://www.thefuturewas8bit.com/minipet4080.html

Source: https://incoherency.co.uk/blog/stories/scamp-lives.html

Source: https://github.com/TomHarte/CP-M-for-OS-X

Source: https://niedzejkob.p4.team/bootstrap/miniforth/

Source: https://www.extremetech.com/computing/323245-risc-vs-cisc-why-its-the-wrong-lens-to-compare-modern-x86-arm-cpus

Source: https://www.youtube.com/watch?v=7A1SzIIKMho

Source: https://www.youtube.com/watch?v=hp1iWCOOchY

Source: https://www.youtube.com/watch?v=wamgUxN1z6o

Source: https://www.youtube.com/watch?v=DbfejwP1d3c

Source: https://www.youtube.com/watch?v=xPTmn63CtTI

6502 Illegal Opcodes demystified

6502 Illegal Opcodes demystified

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.css-xa4zjt{color:var(--chakra-colors-ebn-colors-yellow01);}6502 Illegal Opcodes demystified

6502 Illegal Opcodes demystified

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6502 Illegal Opcodes demystified