Computer Architecture,Languages and operating systems Flashcards
Step 1 to the fetch-execute cycle:
the CPU fetches the necessary data and instructions and store them in its own internal memory locations. To fetch the instruction the CPU uses the address bar. The data is then moved to a special register that will decode the instruction
Step 2 to the fetch-execute cycle:
The CPU decodes the instruction using an instruction set.
Step 3 to the fetch-execute cycle:
Once the CPU has decoded the instruction it executes the instruction. If calculations are needed, this will be carried out by the ALU.
Draw the fetch-execute cycle:
Fetch instruction-Decode instruction-Execute instruction
cache memory:
A portion of memory location within the CPU used for high-speed storage.
Register:
An internal memory location within the CPU that temporarily holds data and instructions during processing.
Accumulator:
The register is used for arithmetic and logic calculations.
Control unit:
this is an internal part of the CPU and it controls the flow of data through the CPU. It also controls the interactions between the different parts of the CPU.
IAS (immediate access store):
This is the memory who found inside a CPU and is used to hold not only data but also the instructions needed to process data. It is also more commonly known as the CPU memory
arithmetic logic unit:
this is an internal part of the CPU that carries out calculations on the data arithmetic part uses the usual operations as such as multiply divide add and subtract. values need to be placed in the accumulator for calculations to be carried out.
Buses:
a bus is a series of conductors or pathways which can be considered a sort of Highway for information.
The 3 separate buses which are used:
1-The data bus carries the data.
2-The address bus carries the memory address.
3-The control bus carries the instructions.
The Von Neumann architecture:
It consists of a single, shared memory for programs and data, a single bus for memory access, an arithmetic unit, and a program control unit. The Von Neumann processor operates fetching and execution cycles.
The purpose of a CPU:
The CPU is responsible for executing a sequence of stored instructions called a program.
The purpose of ROM:
ROM is a special kind of memory that stores the instructions which the computer uses when it ‘boots up’. ROM is a type of memory that retains its data even without power.