1.1 Computer Systems Flashcards
(architecture of the CPU): purpose of CPU, components + features of CPU, Von Neumann architecture
purpose of the CPU
fetch, decode, execute instructions OR process data
what is a register
component holding short-term memory to store addresses/data currently worked on
what is the MAR register
Memory Address Register = store address of next instruction or data to be accessed
MDR register
Memory Data Register = stores data brought from memory/ sent to PC
PC (register)
program counter has address of next instruction to be accessed from memory
purpose of PC in fetch decode execute cycle
points to memory location of next instruction, contents copied to MAR, contents are incremented
purpose of CU
Control Unit = control flow of data in CPU , controls timing signals, controls input and output of data
purpose of cache
stores frequently used data, faster access than RAM so data/instructions can be loaded to CPU quicker
purpose of ALU
Arithmetic Logic Unit = perform arithmetic and logical calculations
effects of using processor with more cores
more instructions carried out simultaneously so more instructions executed at same time
clock speed (how does it affect performance of CPU)
measures (GHz) number of cycles CPU performs per second. - if increased more instructions carried out per second so executed quicker
effects on CPU performance by using bigger cache
more space for frequently used data so more storage that is very fast access so faster fetching of data so faster processing
what is an embedded system
computer system built within another device designed for specific purpose
purpose of embedded system
cheaper than providing personal computer system, can be smaller, device can be automated
examples of embedded systems
dishwasher, SatNav, washing machine, MP3 Player
