6502s are 8bit microprocessors from the 70s developed by MOS Technology. Sweet thing is they come in DIP-40 trough hole packages, although we doubt an emulator based on 7400 logic chips will fit the same package. Check out André’s DIY 6502 computer for the Open 7400 Logic Competition.
I have built a DIY 6502 computer, which is mostly TTL logic only except for 65xx chips and ROMs, but the most TTL-ish part is the blitter: A block transfer engine that DMAs memory area from one location to another. It falls into the “over-complicated” category, it has 30+ 74xx TTL logic chips, with only one CPLD for the sequencer. It can copy from single (e.g. I/O) address to memory or back, can count addresses forwards and backwards, and can even use offsets.
Build something that uses or abuses a logic chip and get amazing boards, tools, and other swag. The Open 7400 Logic Competition promotes awareness of the basic building blocks of modern circuits. Devious geeks ignited the computer revolution with discrete logic computers, what can you do? Details and entry form here.
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