Zenith Data Systems (ZDS) was a ivision of Zenith founded in 1979 after Zenith acquired Heathkit, who had, at that time, recently entered the personal computer market. Headquartered in Benton Harbor, Michigan, Zenith sold personal computers under both the Heath/Zenith and Zenith Data Systems names. Zenith was an early partner with Microsoft, licensing all Microsoft languages for the Heath/Zenith 8-bit computers. Conversely, Microsoft programmers of the early 80s did much of their work using Zenith Z-29 CRT display terminals hooked to central mainframe computers. The early Heath/Zenith computers were based on the Z80 processor and ran either HDOS or CP/M operating systems.