The 6800 was an 8-bit microprocessor designed and manufactured by Motorola in 1974. The MC6800 microprocessor was part of the M6800 Microcomputer System that also included serial and parallel interface ICs, RAM, ROM and other support chips. A significant design feature was that the M6800 family of ICs required only a single five-volt power supply; other microprocessors required three voltages. The M6800 Microcomputer System was announced in March 1974 and was in full production by the end of that year.
The 6800 architecture and instruction set were influenced by the then popular Digital Equipment Corporation PDP-11 mini computer. The 6800 had a 16-bit address bus address that could access 64 KB of memory and a 8-bit bi-directional data bus. It has 72 instructions with seven addressing modes for a total of 192 opcodes. The original MC6800 could have a clock rate of up to 1 MHz. Later versions had a maximum clock rate of 2 MHz.
In addition to the ICs, Motorola also provided a complete assembly language development system. The customer could use the software on a remote timeshare computer or on an in-house mini-computer system. The Motorola EXORciser was a desktop computer built with the M6800 ICs that could be used for prototyping and debugging new designs. An expansive documentation package included datasheets on all ICs, two assembly language programming manuals, and a 700 page application manual that showed how to design a point-of-sale computer terminal.
The 6800 was popular in computer peripherals, test equipment applications and point-of-sale terminals. The MC6802, introduced in 1977, included 128 byte of RAM and an internal clock oscillator on chip. The MC6801 and MC6805 included with RAM, ROM and I/O on a single chip were popular in automotive applications.
Motorola's history in semiconductors
Galvin Manufacturing Corporation was founded in 1928 in Chicago, Illinois and produced their first Motorola brand car radio in 1930. The company name was changed to Motorola in 1947. A research and development center was opened in Phoenix, Arizona in 1949 and they began commercial production of transistors at a new $1.5 million facility in Phoenix in 1955. In 1966 an integrated circuit facility was built in the Phoenix suburb of Mesa. In 1973, they announced plans to build a new plant in Austin, Texas to manufacture MOS integrated circuits. The microprocessor group moved from Mesa to Austin in 1975.
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