History of Microprocessor

4004:- The first commercially available Microprocessor was the Intel 4004 produced in 1971. It contained 2300 PMOS transistors.The 4004 was a 4 bit device intended to be used with some other devices in making a calculator.In 1972, Intel came out with the 8008, which was capable of working with 8 bit words.

8008 :- The 8008 however required 20 or more additional devices to form a functional CPU.

8080:- In 1974 Intel announced the 8080, which had a much larger instruction set than the 8008 and required only two additional devices to form a functional CPU.The 8080 used NMOS transistor, so it operated much faster than the 8008The 8080 is referred as a Second generation Microprocessor.It requires +5V,-5V and +12V supply.

8085:- In 1977, Intel Produced 8085, an upgrade of 8080 that required only a +5V supply.It was a 8 bit Microprocessor.

8088:- Intel Produced 8088, which was the first Microprocessor used in Personal computer by IBM. It has 16 bit registers and an 8 bit data bus and can address up to 1 million bytes of internal memory.

8086:- In 1978 Intel came out with the 8086 which is a full 16 bit Microprocessor.It has a 16 bit data bus and runs faster.It can address 220 or 1048576 memory locations.

80286:- Runs faster than the preceding processors, has additional capabilities and can address up to 16 million bytes.This processor can operate in real mode or in protected mode, which enables an operating system like windows to perform multitasking and to protect them from each other.

80386:-Has 32 bit registers and 32bit data bus.It can address up to 4 billion bytes of memory. The processor supports virtual mode, whereby it can swap portions of memory onto disk

80486:- Has 32 bit registers and 32 bit data bus.High speed cache memory connected to the processor bus enables the processor to store copies of the most recently used instructions and data.The processor can operate faster when using the cache directly without having to access the slower memory.

PENTIUM:-It has 32 bit registers, a 64 bit data bus and separate caches for data and for memory.The Pentium has a 5 Stage pipelined structure and the Pentium II has a 12 stage super pipelined structure.This feature enables them to run many operations in parallel.