Computer Architecture Flashcards
What is a buffer?
Memory used to store information being transferred by the interface
Which bus is used to identify a memory location for reading or writing
Address Bus
Which bus is used to transfer data between processor and memory?
Data bus
What is the job of the ALU?
To perform calculations and arithmetic operations
What is the job of the control unit?
To load, decode and execute instructions
What is the job of the registers?
To act as memory locations used by the processor
What do buses do?
Connect the CPU to main memory
Registers act as temporary storage areas which hold information such as…
The address of the next instruction to be fetched (Program Counter)
Address of the memory location where data is to be written to or read from (Memory Address Register)
(Intermediate) results of arithmetic and logic operations (Accumulator), i.e. data items themselves
When data is read from or written to memory…
The processor sets up the address register with the address of the memory location to be accessed
Read or write line on the control bus is activated
Data is then transferred to or from the data register via the data bus
The total number of memory locations is given as:
2 to the power of the number of lines in the address bus e.g. 16 lines = 2^16 possible memory locations
What are the steps taken by the processor during the fetch-execute cycle?
Transfer contents of program counter into memory address register
Increment the program counter
Activate read line (So transferring instruction to the data register)
Which function of an interface is responsible for telling a user that the printer is out of ink?
Transferring status information
The total number of memory locations which can be used by the processor is determined by…
The number of lines in the address bus
The number of lines in the data bus determines…
The word size of the processor. How much data can be fetched at once.
The purpose of an interface is to
Allow the processor to communicate with peripherals
Processor performance can be improved by
- Using cache memory which has faster access times than RAM
2. increase size of data bus, so more data/instructions transferred at once
Speeding up the processor and reducing the size of transistors will
Improves performance at the expense of additional power consumption and heat dissipation
What is an emulator?
Software which duplicates the function of one computer system into another
What is a virtual machine?
An emulation of a complete computer system - can be used to run alternative operating systems or several copies of a single operating system
A program counter stores the
Address of the next instruction
The accumulator stores the
Result of the last calculation
The address bus is a
Unidirectional bus
Number of lines in the data bus determines the
Word size of the processor - i.e. the number of bits of data/instructions transferred together in one fetch
The number of lines in the address bus determines the
Maximum addressable memory
A virtual machine exists:
In RAM
