0011 – RAM and I/O

Getting to the free-run stage is easy. Where it gets complicated is when you add hardware to make your fancy program counter into a real computer. When you're doing a project like this, its assumed you are willing to put in the time to learn some electronics in order to move forward. Both the journey… Continue reading 0011 – RAM and I/O

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0010 – Free Run and Hex Display

The first test of every new microprocessor  "single-board" project is free-run. Once the CPU, clock, and reset circuitry is in place, we hardwire the data bus to supply the data pins on the 6502 with its opcode NOP (No-Operation). The hexadecimal for the NOP instruction is $EA. This is a simple do-nothing opcode that basically… Continue reading 0010 – Free Run and Hex Display