1.1- Systems Architecture Flashcards
Hardware
The physical things in a computer system, eg. CPU, motherboard
Software
The programs or applications that a computer system runs, eg. operating system
Embedded system
A computer system that has been designed for a dedicated function as part of a bigger system
Embedded system features
Low cost, small, reliable, robust, low power
Purpose of the CPU
-execute the instructions of the programs,
-process data
-manage the rest of the hardware resources
Three main parts in CPU
Control Unit (CU), Arithmetic Logic Unit (ALU), Cache
Control Unit (CU)
-Manage the fetch-execute cycle
-Controls the flow of data in and out the CPU
-Sends signals to direct the operations
Arithmetic Logic Unit (ALU)
Carries out the calculations, logic operations and contains the accumulator
Cache
Very fast memory that stores regularly used data, so the CPU can access it quickly
Memory speed order
- Registers
- Cache
- RAM
Program counter (PC)
Holds the single memory address of the instruction for each cycle
Accumulator
Stores intermediate results of calculations in the ALU
Memory Address Register (MAR)
Holds the single memory address of the data being processed
Memory Data Register (MDR)
Stores the data that is fetched from or to be sent to memory
Memory
Holds the program instructions and data
Higher Clock speed
More instructions can be carried out per second
More Cores
Parallel processing can take place: it can execute separate instructions at once which enables multitasking, so it can process a batch of data faster.
Larger cache
Faster access to more data it needs to process (faster at accessing data than RAM)
fetch execute cycle
-fetch instruction
-decode instruction
-execute instruction
fetch instruction
causes the next instruction and any data involved to be fetched from main memory
address
The address might point to data or a CPU instruction.
Embedded system eg
dishwashers, microwaves, TVs
general purpose computer
designed to run many applications
Register
Small piece of memory inside the processor that can hold one instruction or address
