A set of schematics and programming instructions for a prototype version of the Apple II home computer recently sold for $630,272 from RR Auction, the company said today.

The documents were written by Apple co-founder Steve Wozniak and included five pages of circuit schematics and notes on sheets of graphic paper, a 12-page handwritten programming instruction guide with 28 steps, and six photocopied pages that were headed “Bus Sources,” “System Timing,” “Display,” “Sync Timing & Adr. Gen,” and “Timing,” featuring several annotations.

Wozniak added notations, circuit changes, and programming notes to these pages as he hand-wired the Apple II prototype, and he confirmed their veracity prior to the auction.

Accompanied by a signed letter of provenance from Wozniak: “These documents, circa 1975, are my original Apple II prototype schematics and programming instructions. They are precious. On these work-in-progress diagrams, you can even see my breadboarding technique, where I’d go over drawn connections in red as I soldered the wires in. At the time, I favored using a purple felt tip pen for writing, so it’s interesting to see these notes decades on. The prototype was hand-wired while I was still an engineer at Hewlett-Packard’s Advanced Product Division, where I was involved in the design of hand-held calculators.”

Along with these notes, a functional Apple-1 computer was also sold off, fetching a price of $736,862. Apple-1 machines were the first computers created by Apple and were sold by Steve Jobs out of his parents’ garage. There were only 175 Apple-1 computers created, and less of half of those are still in existence.

 

Other items sold at the auction include a “Battleship” keyboard signed by Steve Jobs and Steve Wozniak that went for $74,535 and a Steve Jobs-signed Monsters, Inc cue sheet that went for $12,501.