In 1977 Mike Markkula, like many users, was unhappy with the time it took to load data from the cassette interface. He made it a company goal to develop a disk system for the Apple II. After studying the Shugart documentation Woz found that he could avoid much of the complex circuitry needed to control a disk head by doing more work in software. In addition, by doing the board layout himself, Woz was able to reduce chip count even further. My Disk II card is an early production unit which is visible by the tin fingers on the card. The Disk II drive is serial #7461 and includes the rainbow ribbon cable that came with the early production units.