In computer architecture, 8-bit integers, memory addresses, or other data units are those that are 8 bits (1 octet or 1 Byte) wide. Also, 8-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size. 8-bit is also a generation of microcomputers in which 8-bit microprocessors were the norm. Mainly we can consider 8-bit microprocessor means 8-bit data or information bus.
for controlling a CRT display, Federico Faggin and his team at Intel designed a chip produced by Computer Terminals Corporation. Later this chip was called as Datapoint. This chip did not meet Datapoint's functional requirement of speed and they decided not to use it. World's first 8-bit general-purpose microprocessor 8008 as developed Intel in the year 1972. The Intel 8008 was used in the famous Mark-8 computer kit. On realizing the potential of this product, Intel introduced the improved 8008. And the respective architecture was known as 8080 microprocessor in the year 1974. The Intel 8080 really created the microprocessor market. Motorola 6800T is the other notable 8-bit microprocessors which was designed for use in automotive and industrial applications, and Rockwell PPS-8, Signetics 2650. They were having innovative and powerful instruction set architecture.
Along with the improvements of integration technologies, the 8224 clock generator and the 8228 system controller chips got integrated and implemented by Intel which was required by the 8080, that is, along with the 8080 microprocessor within a single chip – the Intel 8085. The other improved 8-bit microprocessors include Motorola MC6809 designed for high performance, Zilog Z-80 and RCA COSMAC designed. This was designed and developed for aerospace applications.
Predictions by Moore, in the year 1975, towards exponential growth in the complexity of integrated circuits was true. He also did the forecast of a change for the next decade indicating that the pace of complexity increase would slow to a doubling every two years during the maturation of design capabilities.
Microprocessors dominated as the CPU of digital computers as with the increase in processing power. Earlier to the arrival of microprocessors, CPU was realized from individual SSI chips. As a definition of a microcomputer, we can state that it is a digital computer that uses a single chip microprocessor as its CPU.