1.1 - Systems Architecture Flashcards
CPU
The Central Processing Unit. Used to process all information that is inputted into the computer.
Input
A device, such as a keyboard, a mouse, or a microphone, which puts data into the computer. They take data, and convert it into a form that can be stored on a computer.
Output
A device, such as a monitor, a pair of headphones, or a printer, which shows processed data to the user.
Memory
Unit is used for holding instructions currently being executed, and data that is being used.
Secondary Storage
Used to perform the processing, and, as a result of processing input, may generate data that is then stored.
Von Neumann Architecture
A processing unit design, designed by John Von Neumann. The idea is to hold both programs and data in memory.
Cache
A very fast memory, close to the CPU, used to temporarily hold data or instructions that are likely to be needed again by the processor in the course of running a program.
Fetch-Decode-Execute Cycle
When a computer is run, it has to first be loaded into main memory. From here it can by accessed by the processor, which runs each instruction in turn. The instruction is fetched, decoded and then executed.
ALU
The Arithmetic Logic Unit. Carried out logical operations, shift operations and arithmetic operations.
Registers
A special very fast memory location within the CPU used in the execution of instructions. Includes the MAR, MDR, PC and ACC.
MAR
Memory Access Register, holds the address of an instruction
MDR
Memory Data Register, hold data or a program instruction temporarily
PC
Program Counter, holds the memory address of the next instruction to by processed
ACC
Accumulator, a special-purpose memory location in which results of operations carried out in the ALU are temporarily stored.
