Back in 1974, the original schematic for the 6502 was sketched out by hand on a drafting board. (In contrast, today’s design methodology has hundreds of engineers working on hundreds of computers creating archived digital files of their work when collaborating on today’s microprocessors.) The creator of the 6502’s schematic doesn’t know where that document is today, and very little information on how the chip was created survives. Further, in the more than 35 years since its design, the understanding of how this remarkable chip performed its functions was lost.