The 4004 is the world's first
microprocessor. The 4004 was created at Intel with Ted Hoff and
Federico Faggin as the lead designers. The 4004 provided a new tool to the
world. Up to that time and semiconductors and IC's were built for a
specific purpose. The 4004 was the first semiconductor device that
provided, at the chip level, the functions of a computer.
The 4004 contains the two basic architectural building
blocks that are still found in today's microcomputers: the arithmetic and
logic unit and the control unit. The Intel 4004 ran at a clock speed of
108 kHz and contained 2300 transistors. By the time it was in production
the clock speed was increased to 500kHz and later to 740kHz. It processed
data in 4 bits, but its instructions were 8 bits long. The 4004 addressed
up to 1 Kb of program memory and up to 4 Kb of data memory (as separate
entities). It had sixteen 4-bit (or eight 8-bit) general purpose
registers, and an instruction set containing 45 instructions.
The 4004 family is also referred to as the MCS-4.