Intel 8080

  • Intel
  • AMD
  • NEC
  • Siemens AG

The Intel 8080 is a 1974 8 -bit microprocessor introduced in NMOS technology from Intel. He is generally regarded as the first full-fledged microprocessor. As a successor to the Intel 8008 instruction set was to be this source-code compatible, but not binary compatible, so programs had to be re-assembled.

Architecture and use

The design with 40 pins enabled an address with 16 bits, so the 8080 could address 64K of memory. In addition, 256 were from the address range independent input / output registers are connected.

He had seven 8- bit registers, six of which could be combined into three 16 -bit registers, and a stack pointer ( stack pointer ) and a program pointer with 16 bit. The operating system CP / M was developed for the 8080 and put almost a decade, the predominant system for microcomputers is similar to later MS -DOS.

Was used in the 8080 control devices (such as cruise missiles ) and the first PCs ( and Others Micral, IMSAI and Altair 8800 ).

Apart from the actual processor is a system required by 8080 two more blocks: a separate clock generator ( 8224 ) and a bus controller ( 8228 ). Appeared in 1976 the successor of 8085, which already included their functions. However, he was not very successful, since in the same year Zilog Z80 with the brought out a 8080 -compatible but highly advanced processor.


  • Supply voltages: 12 V, 5 V, -5 V
  • Frequency: 2 MHz
  • Number of transistors: 6,000 at 6 microns
  • Data bus: 8 bits
  • Address bus: 16 bit
  • Addressable memory: 64 KB

Peripheral Devices