Retest Flashcards
State the purpose of the CPU
it fetches, decodes, and executes instructions
State two functions of the CU
It is part of the decode section of the computer and decodes instructions. It also controls how data moves around the CPU
Describe the purpose of the memory data register
It holds the data that has been fetched from or to be written to main memory
Example of an embedded system
A calculator - it fetches the inputted numbers, decodes them and executes the calculations before outputting the numbers
What things do you need to consider for suitable storage
6 Cost Speed Portability Reliability Durability Capacity
How many bits per character is Unicode
16
How many bits per character is ASCII
7
With 8 bits per pixel how many colours can be stored
256
How to calculate image file size
Height x width x colour depth
How to calculate sound file size
sample rate x duration x bit depth
How to calculate a text file size
bits per character x number of characters
How to convert real sound into digital sound
The sound is received through a microphone
It is digitalized using an analogue to digital converter
It is sampled at regular intervals
The values are rounded depending on resolution/bitdepth
Stored as binary
What is sample rate
number of samples taken per second (hertz)
What is sample resolution
number of bits used to store each sample
What is sample size
number of seconds over which the sample was taken
