Structure And Function Of The Processor Flashcards
What is the ALU?
It completes all the arithmetic and logical operations. (Arithmetic and Logic Unit)
What does the arithmetic operations include?
It includes all mathematical operations such as addition and subtraction on fixes or floating point numbers.
What do Logical operations include?
It includes Boolean logic operations such as And, Or, Not, Xor.
What is a Control Unit?
It is the component of the processor which directs the operations of the CPU.
What jobs does the The Control Unit have?
- Controlling and coordinating the activities of the CPU
- Managing the flow of data between the CPU and other devices
- Accepting the next instruction
- Decoding instructions
- Storing the resulting data back in the memory
What are registers?
Registers are small memory cells that operate at a very high speed.
What are registers used for?
They are used to temporarily store data and all arithmetic, logical and shift operations in these registers.
Purpose of a Program counter, PC (register)?
Holds the address of the next instruction to be executed.
Purpose of the accumulator, ACC (register)?
It stores the results from the calculations
Purpose of the Memory Address Register, MAR (register)?
Holds the address of a location that is to be read from or written to.
Purpose of the Memory Data Register, MDR (register)
Temporarily stores data that has been read or data that needs to be written.
Purpose of the Memory Data Register, MDR (register)
Temporarily stores data that has been read or data that needs to be written.
Purpose of the Current Instruction Register, CIR (register)
Holds the current instructions being executed, divided up into operand and opcode.
What are buses?
Buses are a set of parallel wires which connect two or more components inside the CPU.
What are the 3 buses and what are they called collectively?
Data bus, control bus, address bus and collectively they are called the system bus.
What is the width of the bus?
It is the number of parallel wires the bus has. It is directly proportional to the number of buts that can be transferred simultaneously at any time.
Typical bus width?
8, 16, 32, 64 wires wide
What is a data bus?
It is a bi-directional bus (bits can be carried both ways)
What is a data bus used for?
It is used for transporting data and instructions between components.
What is the address bus?
It is used to transmit the memory addresses specifying where data is to be sent to or retrieved from.
What is the width of the address bus?
The width is proportional to the number of addressable memory locations.
What is a control bus?
It is a bi-directional bus used to transmit the control signals between internal and external components.