Karteikarten
CPU Things + maybe RAM ROM + Virtual memory
Karten in diesem Stapel (11)
- 1What is the cpu?The CPU is the like the brain of the computer. It is the Central Processing Unit.
- 2What registers are in the CPU?MAR (Memory Address Register),
MDR (Memory Data Register),
Program Counter,
Accumulator
ALU (Arithmetic Logic Unit)
General Purpose Registers - 3What is the Program CounterA special purpose register that holds the address of the next instruction to be executed
Stored in the CU and incremented (increase) after fetching an instruction.
This moves it on to the point for the next instruction o be executed.
The current instruction is moved to the Current Instruction Register (CIR) - 4What does the general purpose registers do?Hold data, such as numbers during arithmetic calculations
Some architectures have just a single register called the Accumulator.
This is where arithmetic and logic results are temporarily stored.
The result is stored in the accumulator but the original data is located in RAM.
It speeds up the storage and retrieval of calculations. - 5What does the ALU (Arithmetic logic unit) do?Logical operations,
shift operations and
arithmetic operations
Basically does the calculations for the CPU. - 6What are the two memory registers?MAR(memory address register)
MDR(memory data register) - 7What does the MAR do?The MAR holds the address of the current instruction being executed.
The MAR also keeps track and knows where the data is located and location of the data that needs to be accessed. - 8What does the MDR do?The MDR stores the actual data that is being processed.
It acts as a buffer and holds the data that is copied from the RAM, ready for the CU to process.
Once it is ready for the data it retrieves it from the MDR - 9What is the cycle that the CPU performs?Fetch - causes the next instruction and any data involved to be fetched from main memory
Decode - decodes the instruction
Execute - carries out the instruction
Then repeat - 10What does PC and CIR stand for?Program counter - The Program Counter points to the next instruction that needs to be executed
Current instruction Register - Holds the current instruction to be executed - 11What does the CU (Control Unit) do?The control unit coordinates all of the activities taking place within the CPU.
Generally compared to a conductor of a orchestra.