alt Hacker NewsI have to say as a 6502 assembly programmer I have wasted many hours of my life tracking down the same issue in my code (forgetting to put an # in front of an immediate value and thus accidentally doing a memory access instead). Often it's like this case too where things might accidentally work some of the time.
Worse than the floating-bus in this example is when it depends on uninitialized RAM which is often consistent based on DRAM so the code will always work on your machine/emulator but won't on someone else's machine with different DRAM chips (invariably you catch this at a demoparty when it won't run on the party machine and you only have 15 minutes to fix it before your demo is about to be presented)
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6502 was my first assembly language, and I always thought of instructions like "LDA #2" as "load A with the number 2" versus LDA 2 (load A with what's in memory location 2).
This is the kind of situation where feeding your code through an LLM can actually be helpful: they're really good at spotting the kind of errors/typos like this that have a profound impact but which our eyes tend to all to easily scan over/past.
Was there ever an architecture that used dynamic memory with a 6502 CPU? In my (limited?) experience, that platform always had static RAM.