4.7.1 Computer Architecture and Organisation Flashcards
(20 cards)
Define Processor (CPU).
A complex chip of transistors capable of executing programs, computing data to outputs, and supervising the operation of a computer system.
Define Main Memory.
A data store for instructions for the processor that can be directly addressed by the processor.
Define RAM.
RAM is Random Access Memory.
- volatile (does not store without power)
- temporary storage for active processes.
Define ROM.
ROM is Read Only Memory.
- non-volatile
- stores essential boot-up instructions
Define Addressable Memory.
The concept that each memory location is identified with a discrete unique address. And that its contents can be accessed by its address.
Define Buses.
A set of parallel connections that allow internal components to communicate and exchange data.
Define Address Bus.
A bus that carries the memory location address of the register the data is being carried to or from.
What does the Address Bus do?
The address bus transports memory addresses, determining where data is read/written.
It is uni-directional, from the processor to main memory or I/O controllers.
Define Data Bus.
A bi-directional bus for carrying data and instructions between the processor and memory.
What does the Data Bus do?
The data bus transfers data and instructions to and from different components of the system.
It is bi-directional between the processor, main memory and the I/O controllers.
Define Control Bus.
A part of the CPU that controls and manages the execution of instructions. It sends control signals to coordinate execution and controls Fetch-Decode-Execute cycles and buses.
What does the Control Bus do?
The control bus sends control signals that regulate the operation of computer system, and also carries the computer’s clock signal.
It is bi-directional between processor, main memory and I/O controllers.
Define I/O controllers.
An interface that allows the processor to communicate with Input/Output devices connected to the computer.
Describe the purpose of I/O controllers.
Facilitates the communication between the processor and external devices like keyboards and monitors.
All peripheral (external) devices are connected to the processor through I/O controllers, allowing communication of data between processor and external hardware devices.
Each device has its own I/O controller.
Define Von Neumann Architecture.
A computer architecture where a single control unit manages program control via a linear sequence of fetch-decode-execute cycles. Data and instructions are held in the same memory.
Describe Von Neumann Architecture.
Both the instructions and data are stored in main memory.
Uses the same address bus and data bus for transferring data/instructions.
Suitable for general purpose computers, allows users to switch between tasks.
Define Harvard Architecture.
A computer architecture that stores data and instructions in separate memories to allow the next instruction to be read while data is currently being read or written.
Describe Harvard Architecture.
Separate memory for instructions and data.
Separate data and address buses used by the processor.
Suitable for embedded systems for performance optimization.
Compare Von Neumann Architecture with Harvard Architecture.
Memory and buses:
- Von Neumann: One main memory for both instructions and data. (could be exploited by hackers)
- Harvard: Separate memory and buses for instructions and data. (More secure, data and instructions can be accessed simultaneously -> higher processor performance.)
Define Pipelining.
A method that breaks the execution of instructions into separate steps carried out by different processor units in sequence, much like an assembly line.
This allows for multiple instructions to be in various stages of execution simultaneously, optimizing CPU time and significantly boosting instruction throughout.
