Computer Organisation Chapter Page • Control unit: To control the overall operations of the computer through signals. • Registers (Internal Memory): They are used to hold the instruction and data for the execution of the processor. Characteristics of Microprocessors A Microprocessor’s performance depends on the following characteristics: a) Clock speed b) Instruction set c) Word size a) Clock Speed Every microprocessor has an internal clock that regulates the speed at which it executes instructions. The speed at which the microprocessor executes instructions is called the clock speed .
Clock speed is measured in MHz (Mega Hertz) or in GHz (Giga Hertz). b) Instruction Set A command which is given to a computer to perform an operation on data is called an instruction . Basic set of machine level instructions that a microprocessor is designed to execute is called as an instruction set . This Speed Measurement Hertz – abbreviated as Hz is the standard unit of measurement used for measuring frequency.
Since frequency is measured in cycles per second, one hertz equals one cycle per second. Hertz is commonly used to measure wave frequencies, such as sound waves, light waves, and radio waves. For example, the average human ear can detect sound waves between and , Hz. Sound waves close to Hz have a low pitch and are called "bass" frequencies.
Sound waves above , Hz have a high pitch and are called "treble" frequencies. While hertz can be used to measure wave frequencies, it is also used to measure the speed of computer processors. For example, each CPU is rated at a specific clock speed. This number indicates how many instruction cycles the processor can perform in every second.
Since modern processors can perform millions or even billions of instructions per second, clock speeds are typically measured in megahertz or gigahertz. instruction set carries out the following types of operations: • Data transfer • Arithmetic operations • Logical operations • Control flow • Input/output c) Word Size • The number of bits that can be processed by a processor in