Information Coding Systems Flashcards
What is an Information Coding System?
A system used to match characters to character codes
What is a character code
A decimal digit used to represent a character
What does ASCII stand for
American Standard Code for Information Interchange
What is Unicode
An information coding system that uses anywhere from 8 bits to 48 bits per character
What is ASCII
A 7 bit information coding system
How many bits can ASCII represent
128 (2^7)
Advantages of Unicode to ASCII
Representation of a much wider range of different characters
What is a Parity Bit
A single bit added to a transmission that can be used to check for errors
How is the value of a parity bit determined
It is based on the transmitted data itself
What are the two types of parity bit
Even Parity and Odd Parity
How does Majority Voting work
Each bit of the data is transmitted multiple times - the most commonly occurring value from the received data is taken to be correct
Disadvantage to Majority Voting
Much larger volume of data is being transmitted which means it takes longer
What is a Checksum
Adding a value determine by the data to transmitted data
What is a check digit
A type of checksum in which only a single digit is added to the transmitted data
How do to a check digit
Calculate positional multiples and sum
Use MOD 11 to calculate remainder
Deduct remainder from 11 to produce check digit
