Coding Text Flashcards
(13 cards)
What is a spare bit used for?
Either a parity bit or to give an extra 128 characters.
What is ASCII?
A 7 bit encoding system, each character represented by a unique number.
What is Unicode?
Unicode is a 8,16 or 32 bits system which represents a wider range of characters.
What are two advantages of Unicode?
-Universal standard for character encoding
-Supports many languages
What are two disadvantages of Unicode?
-Unicode uses more space and memory.
-More bits are needed for non ASCII characters
What is a parity bit?
A bit used for error detection, and computers use either odd or even parity and data checked at both sending and receiving ends.
Using odd parity what 8 bit of code is sent for 00110000?
100110000
Explain how even parity works
The even parity system is sent a code where it ensures if there is an even number of 1s, if even parity bit is 0 else if odd parity set to 1. Once receiver receives transmission it counts 1s, if it is even data accepted else transmission sent again.
Explain how odd parity works
The odd parity system is sent a code to which it ensures there is an even number of 1s. If it is even the parity is set to 1 else if odd parity set to 0. Once reciever recieves transmission it counts 1s if odd it is accepted otherwise transmission is sent again.
What is Majority Voting?
1) Each bit is transmitted 3 times
2) If set of 3 doesn’t have the same values majority voting will show and correct errors.E.g 010-1 is the error therefore transmission should be 000 according to majority vote.
What are disadvantages of Majority voting?
Not 100% foolproof and less efficient
What are majority voting advantages?
It identifies and corrects the errors
What is Check digit?
A digit is added to end of data to check if data is accurate. Check digits used with barcodes and books.
