Microprocessor
A microprocessor (also known as a CPU or central processing unit) is a complete computation engine that is fabricated on a single chip. It uses assembly language which is the native language of a microprocessor. The microprocessor can execute a collection of machine instructions that tell the main processor what to do.
Using its ALU (Arithmetic/Logic Unit), a microprocessor can perform mathematical operations like addition, subtraction, multiplication and division. Modern microprocessors contain complete floating point processors that can perform extremely sophisticated operations on large floating point numbers.
A microprocessor does three basic things:
History
In the 1960s, processors were constructed out of small and medium-scale ICs, each containing tens of transistors to a few hundred transistors. Often multiple boards would have to be interconnected in a chassis.
In NASA’s Apollo space missions to the moon in the 1960s and 70s, all on board computations for primary guidance, navigation, and control were provided by a small custom processor called "The Apollo Guidance Computer"; which used wire wrap circuit boards whose only logic elements were three-input NOR gates.The integration of a whole CPU onto a single chip or on a few chips greatly reduced the cost of processing power.
Continued increases in microprocessor capacity has rendered other forms of computers almost completely obsolete with one or more microprocessors used in everything from the smallest embedded systems and handheld devices to the largest supercomputers and mainframes.
The first microprocessors that emerged in the early 70s were used for electronic calculators, which used binary-coded decimal arithmetic on 4-bit words. Other embedded uses of 4-bit and 8-bit microprocessors, such as terminals, various kinds of automation, and printers then soon followed. Affordable 8-bit microprocessors with 16-bit addressing led also to the first general-purpose microcomputers from the mid-70s and on.
Using its ALU (Arithmetic/Logic Unit), a microprocessor can perform mathematical operations like addition, subtraction, multiplication and division. Modern microprocessors contain complete floating point processors that can perform extremely sophisticated operations on large floating point numbers.
A microprocessor does three basic things:
- A microprocessor can move data from one memory location to another.
- A microprocessor can make decisions and jump to a new set of instructions based on those decisions.
- The number of transistors available has a huge effect on the performance of a processor.
History
In the 1960s, processors were constructed out of small and medium-scale ICs, each containing tens of transistors to a few hundred transistors. Often multiple boards would have to be interconnected in a chassis.
In NASA’s Apollo space missions to the moon in the 1960s and 70s, all on board computations for primary guidance, navigation, and control were provided by a small custom processor called "The Apollo Guidance Computer"; which used wire wrap circuit boards whose only logic elements were three-input NOR gates.The integration of a whole CPU onto a single chip or on a few chips greatly reduced the cost of processing power.
Continued increases in microprocessor capacity has rendered other forms of computers almost completely obsolete with one or more microprocessors used in everything from the smallest embedded systems and handheld devices to the largest supercomputers and mainframes.
The first microprocessors that emerged in the early 70s were used for electronic calculators, which used binary-coded decimal arithmetic on 4-bit words. Other embedded uses of 4-bit and 8-bit microprocessors, such as terminals, various kinds of automation, and printers then soon followed. Affordable 8-bit microprocessors with 16-bit addressing led also to the first general-purpose microcomputers from the mid-70s and on.
Structure
The internal arrangement of a microprocessor varies depending on its age and its intended purpose. The complexity of an integrated circuit is bound by physical limitations of the number of transistors that can be put onto one chip, the number of package terminations that can connect the processor to other parts of the system, the number of interconnections that’s possible to make on the chip, and the amount of heat that the chip can dissipate.
At minimal, a microprocessor may only include an arithmetic logic unit (ALU) and a control logic section. The ALU performs operations such as addition, subtraction, and operations such as AND or OR. Each operation of the ALU sets one or more flags in a status register, which indicates the results of the latest operation. The logic section retrieves instructional operation codes from memory, and initiates whatever sequence of operations of the ALU required to carry out the instruction. A single operation code might affect many individual data paths, registers, and other elements of the processor.
Occasionally, the physical limitations of integrated circuits made practices such as bit slice approach necessary. Instead of processing all of a long word on one integrated circuit, multiple parallel circuits processed subsets of each data word. While this requires extra logic to handle, the result was a system that could handle 32-bit words using integrated circuits with a capacity of 4 bits each.
At minimal, a microprocessor may only include an arithmetic logic unit (ALU) and a control logic section. The ALU performs operations such as addition, subtraction, and operations such as AND or OR. Each operation of the ALU sets one or more flags in a status register, which indicates the results of the latest operation. The logic section retrieves instructional operation codes from memory, and initiates whatever sequence of operations of the ALU required to carry out the instruction. A single operation code might affect many individual data paths, registers, and other elements of the processor.
Occasionally, the physical limitations of integrated circuits made practices such as bit slice approach necessary. Instead of processing all of a long word on one integrated circuit, multiple parallel circuits processed subsets of each data word. While this requires extra logic to handle, the result was a system that could handle 32-bit words using integrated circuits with a capacity of 4 bits each.
Overview
What it is: it incorporates the functions of a computer's central processing unit on one or more integrated circuits. It’s a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and provides results as output. Microprocessors operate on numbers and symbols represented in the binary numeral system.