The Cyclone, was a vacuum tube computer, built by Iowa State College at Ames, Iowa. The computer was commissioned in July 1959. It was based on the IAS architecture developed by John von Neumann. The prototype was ILLIAC, the University of Illinois Automatic Computer. The Cyclone used 40-bit words, used two 20-bit instructions per word, and each instruction had an eight-bit op-code and a 12-bit operand or address field. In general IAS-based computers were not code compatible with each other, although originally math routines which ran on the ILLIAC would also run on the Cyclone.