The microprocessor is the Central Processing Unit (CPU) of digital computers and it is constructed with IC technology.
The microprocessor is a data-processing unit. Data processing includes both computation and data handling. Computation is performed by logic circuits called the Arithmetic Logic Unit (ALU). The ALU is used to perform add, subtract, AND, OR, XOR, compare, increment, and decrement functions. The ALU cannot perform any functions without control signals. In order to process data, the microprocessor must have control logic which instructs the microprocessor how to decode and execute the program.
There are four steps in the operation of a microprocessor. In the first step, the microprocessor fetches an instruction and in the next step, the control logic decodes what the instruction has to do. Then decoding is done in the third step and in the last step, the microprocessor executes the instruction.
Architecture of a Microprocessor
The microprocessor always operates in binary digits: 0 and 1, known as bits. Bit is an abbreviation for â€˜binary digitâ€™ which can be represented in terms of voltages. The microprocessor recognises and processes a group of bits, called the word. Microprocessors are classified according to their word length such as 8-bit, 16-bit, 32-bit and 64-bit microprocessors. The microprocessor ICs are programmable so that instructions can be executed by the microprocessor to perform given tasks within its capability. The instructions are stored in a storage device which is called the memory, and the microprocessor can read instructions from memory.