The MOnSter 6502

You might have seen my discrete 555 and 741 IC electronics kits. Well, a while back I had this idea about creating a discrete version of a microprocessor, but it just sounded too difficult, time consuming, or impractical. And part of me didn’t want to do it, because it just sounds so tedious to design–at every stage, I was secretly hoping to find a show-stopping problem. But part of me was really interested to see if it could be done. At dinner, Windell and I went through a thought experiment to see if it would even be possible. We weren’t sure how many transistors were in a 6502 (more than 1,000 but less than 10,000). If four surface mount transistors can fit in a square centimeter, then the board would need to be about 1,000 square centimeters, or about 32cm (13in) on a side, which is not as huge as we originally thought. Darn it, time to investigate further! The hard work of reverse engineering the actual 6502 has already been done by the folks at Visual6502.org. I was able to extract the netlist from their Javascript simulation, which contains a list of all the transistors and every single wire connecting them together.”

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