CPU Flashcards
What does CPU stand for?
Central Processing Unit
What is the function of CPU?
Responsible for gathering and executing instructions in their order, as well as controlling peripherals (devices)
What are the components in a CPU?
Arithmetic and Logic Unit (ALU)
Control Unit (CU)
Registers
Program Counter
System Clock
What does ALU do?
Performs execution of instructions including arithmetic, logic and comparison operation
What is arithmetic operation?
Addition, subtraction, multiplication and division
What is logic operation?
True and false
What is comparison operation?
Greater than, equal to, less than
What does CU do?
Directs and coordinates operations in the computer;
Performs fetch-execute cycle;
‘The boss of CPU’
What does register do?
Small but fastest storage/memory to the CPU
What does program counter do?
Register that stores the address of the currently executing instruction
What does system clock do?
Microprocessor that regulates timing and speed of computer system’s functions
What is Fetch-Execute cycle?
A process in which a computer receives data and determines what to do with it
Process of the Fetch-Execute cycle?
- Fetch - Decode - Execute - Store -
What is the fetch process about?
CPU retrieves instructions from a system hard drive or SSD and stores them in a register
What is the decode process about?
CPU determines which system components are required in the execution of the instruction and stores them in a register
What is the execute process about?
CPU assigns relevant actions to the relevant system components in order to carry out the instructions, processing the actual data
What is the store process about?
Processed data is stored in memory locations (Registers, HDD, SSD)
What is instruction cycle?
Fetch and decode process
What is execution cycle?
Execute and store process
Explain the whole process of fetch-execute cycle in Little Man Computer model
- receives value from program counter indicating where to fetch the instruction
- decodes the instruction by reading the instruction set, head to the memory to get the data
- follows instruction and perform task, then tell program counter to +1 for next instruction
