2.3 Fundamentals of computer organisation and architecture Flashcards
Define processor
A device that carries out computation on data by following instructions in order to produce an output. Electrical pulses timed by the computer’s clock are controlled by transistors which represent parts of an instruction being carried out
Define main memory
Stores data and instructions that will be used by the processor
Define fetch execute cycle
The continuous process carried out by the processor when running programs
Define RAM
Random Access Memory (RAM) stores data and can be read from and written to. This memory is volatile, meaning that if it data stored on it is not saved before the computer is shut down the data will be lost
Define ROM
Read only memory (ROM) stores data and can be read from but cannot be written to. This is often used to store instructions relating to the setup of the computer
Define bus
Microscopic parallel wires that transmit data between internal components
Define data bus
Transfers data between the processor and memory
Define input/output controller
Controls the flow of information between the processor and the input and output devices
Define word length
The number of bits that can be addressed, transferred, or manipulated as one unit
Define address bus
Used to specify a physical address in memory so that the data bus can access it
Define addressable memory
The concept that data and instructions are stored in memory using discrete addresses
Define control bus
Controls the flow of data between the processor and other parts of the computer
Define Von Neumann architecture
A technique for building a processor where data and instructions are stored in the same memory and accessed via buses
Define Harvard architecture
A technique for building a processor that uses separate buses and memory for data and instructions
Define stored program concept
The idea that instructions and data are stored together in memory
Describe the stages of the fetch execute cycle
- Fetch: the processor fetches the program’s next instruction from memory. The instruction will be stored at a memory address and contain the instruction written in binary code
- Decode: the processor works out what the instruction at that binary address means
- Execute: the processor carries out the instruction, this encompasses tasks such as reading data from memory, performing a calculation, or writing data to memory
Define control unit
The part of the processor that manages the execution of instructions
Define arithmetic logic unit
The arithmetic logic unit (ALU) is the part of the processor that processes and manipulates data
What is the clock?
A device that generates a signal used to synchronise the components of a computer
Define register
A small section of temporary storage that is part of the processor, which stores data or control instructions during the fetch execute cycle
Define status register
Keeps track of the various functions of the computer such as if the result of the last calculation was positive or negative
Define interrupt register
Stores details of incoming interrupts
Define current instruction register (CIR)
Register that stores the instructions that the CPU is currently decoding / executing
Define program counter (PC)
Register that stores the address of the next instruction to be taken from main memory into the processor