Intel 8080

The Intel 8080 was an early CPU designed and manufactured by Intel. It was released in April 1974 running at 2 MHz, and is generally considered to be the first truly usable microprocessor design. It was used in many early computers, and formed the basis for machines running CP/M.

The Intel 8080 was the successor to the Intel 8008 (with which it was assembly language source-compatible because it used the same instruction set developed by Computer Terminal Corporation). The 8080's large 40 pin DIP packaging permitted it to provide a 16-bit address bus and an 8-bit data bus. It had seven 8-bit registers (six of which could also be combined as three 16-bit registers), a 16-bit stack pointer to memory which replaced the 8008's internal stack and a 16-bit program counter. It also had 256 I/O ports (so I/O devices could be connected without needing to allocate any addressing space as is required for memory mapped devices).

Shortly after the 8080, the Motorola 6800 was introduced.

The first single-board microcomputer was built on the basis of the 8080.

See also: List of Intel microprocessors, Zilog Z80

This article (or an earlier version of it) contains material from FOLDOC, used with permission.