The NEC TK 80 is a 8080-cpu Training Kit (hence the "TK") computer sold at the end of the 70's. It is considered the first japanese home-computer. It was firstly aimed at technicians, but it met a great success with first computer hobbyists. It was often sold as a kit.
The systems is directly programmed in machine-code through the hexadecimal keyboard. There are 9 "function" keys on this keyboard : RET, RUN, STORE DATA, LOAD DATA, RESET, ADRS SET, READ INCR, READ DECR, WRITE INCR.
Information is displayed on the built-in 7-segments LED display (1 line, 8 characters).
The TK-80E is low-cost TK-80. The CPU and some chips are slightly different (uPD8080AD -> uPD8080AFC, uPD8228D -> uPD8228C, uPD454D -> uPD464C, uPD5101E -> uPD2101AL-4), thus reducing the production cost (ceramic -> plastic). Of course the TK-80E was less expensive.
The TK-80 BS was a "Basic Station" model. It was composed of a TK-80 board with a BASIC ROM built-in, 7k RAM and an alphanumeric keyboard. Furthermore there was the Compo BS/80 which was a TK-80 with its Basic extension within a nice moulded plastic case.
The TK-80 was used as a base for the PC-8001, the PC-8801 and the PC-9801.
Picture courtesy of Electric Brain Museum.