Architecture Flashcards
Discuss the difference between RAM and Cache memory
«RAM: Fast read and write access and is volatile, used to store data and currently running programs. It is needed as most data in computers is stored in “storage media” and for the processor to be able too work on data, the programs need to be copied to RAM first.
«Cache: Fast form of RAM located close to the CPU. Is volatile and is used to store frequently used data from main memory. Low capacity so RAM is still needed in order to avoid constantly accessing things from slow storage media
What three components does the CPU contain?
Arithmetic and Logic Unit (ALU), the control unit, cache memory
What is the purpose of the ALU
Performs calculations such as addition, performs boolean operations, performs shift operations.
What is the purpose of the Control Unit
Directs the flow of commands including loops, data, in and out memory and in and out registers. Also fetches and decodes instructions
What is the purpose of Cache?
Stores most recently accessed data so that if it is required it can be accessed in less time.
What is serial transmission and what is an advantage of it?
Data is sent one bit at a time along the same data line. It requires only two wires compared to 8 or 16 in parallel, can be long distance, simpler interface.
What is parallel transmission and what is an advantage of it?
All bits in a byte are sent simultaneously along separate lines. Data transmission is faster than with serial transmission.
How does a computer make use of RAM?
Computer uses RAM to store programs while they are being executed- being run/processed
What is a dual core CPU? What could the benefits of it be?
It has two processors which carry out two instructions at same time. Means computer can run program faster.
What is meant by 5GHz
This is the clock speed of processor. Means 5 billion cycles per second.
Explain why a CPU needs a control unit
Control the other components by following instructions. It organises the transfer of data using internal memory/special registers
What happens during the Fetch Execute Cycle?
The control unit gets each instruction in sequence. It decodes and then carries it out by sending control signals to other parts of computer
How is data wrote to an optical disk?
A laser beam is used, which burns pits into the surface. to represent binary data in a single spiral track. To read data a laser beam is shone onto surface of disk which is reflected which detects the presence or absence of pits.
What are four advantages of using optical disks as a secondary storage media?
Has high storage capacity, is portable, is durable, has relatively fast read write speeds.
Describe how the program counter is used in the Fetch Execute Cycle.
It contains the location of the next instruction to be executed, contents are incremented when the instruction has been fetched.
