In 1976, they started marketing a multi-user, display-based product, based on the Zilog Z80 processor. Typical installations had a master unit (supplying disk storage) connected to intelligent diskless slaves which the operators used. Connections were via dual coax using differential signaling in an 11-bit asynchronous ASCII format clocked at 4.275 MHz. This product became the market leader in the word processing industry. In addition to calculators and word processors, Wang's company diversified into minicomputers in the early 1970s. The Wang 2200 was one of the first desktop computers with a large CRT display and ran a fast hardwired BASIC interpreter. The Wang VS system was a multiuser minicomputer whose instruction set was very close to the design of IBM's System/370. It was not binary-compatible because register usage conventions and system call interfaces were different. The Wang VS serial terminals could be used in data processing mode and word processing mode. They were user-programmable in data-processing mode and used the same word processing software as the earlier dedicated word processing systems.