5.5 information coding system Flashcards
ASCII stand for
american standard code for information exchange
ascii uses ___ bits
7
7 bits can represent
128 different characters
unicode uses anywhere from __ to __ bits
8 to 48
Parity bit
single bit added to transmission
checks for errors
two types of parity bit
even and odd
in even parity
makes the total number of 1’s even
in odd parity
total number of 1’s odd
if any error is detected in parity check
asks recipient to retransmit
majority voting
each bit send data multiple times
most common value taken to be correct
majority voting also
corrects the error
disadvantage of majority voting
takes time
check sum
value appended to transmitted data
once received recipient removes checksum
check is carried out to make sure checksum matches transmitted data
check digit
a check digit is a type of checksum
single digit added
