the manufacturing division split its single research & development department into two, renaming it to Research & Development No. 1 (R&D1) and creating the Nintendo Research & Development No. 2 (R&D2) department. After the split, Yokoi remained general manager of R&D1. 1979-1988: Game & Watch In the late 1970s, Yokoi saw a bored Japanese salaryman playing with a calculator on the Shinkansen high-speed train. This was the inspiration for the creation of the Game & Watch series, a line of handheld electronic games, with each system featuring a single game to be played on an LCD screen in addition to a clock, an alarm, or both. Regardless, it was confirmed that Yokoi was inspired by calculators to develop the line, even using calculator integrated circuits in the systems and button cells to power them. Although Nintendo competitors Mattel and Tomy had already produced portable games, they were mostly bulky systems with low-resolution LED displays and uninspiring gameplay. Yokoi exploited the cheapness of LCDs, producing cheap and light systems, starting in 1980. He would later call this principle Lateral Thinking of Withered Technology: using seasoned technology in radical ways; a principle that echoed throughout Nintendo until the present day. In 1980, Game & Watch: Ball was the first release of the Game & Watch Silver series, called after its metallic face-plate. Sales weren't reportedly "astonishing", but they were enough to persuade Nintendo to continue developing new titles. The series saw a total of 5 systems, all released during that year. In 1981, Game & Watch: Manhole debuted the Gold series, which was fundamentally the same system with a golden face-plate. It saw only 3 titles which were also released during the same year. In mid-1981, Game & Watch: Parachute was released, debuting the Wide Screen series, sporting a 30% larger display. The series saw a total of 10 titles released until early 1982. The limitations of the LCD display prompted Yokoi and his team to introduce the Multi Screen series with the release of Game & Watch: Oil Panic in mid 1982, adding another screen to potentially double the amount of gameplay each title could offer. The next title of the series was Game & Watch: Donkey Kong a port of the hugely successful Donkey Kong arcade game. Unable to use a joystick like the original game, as it would reduce the system's portability, Yokoi began researching for solutions. Early Game