Difference between revisions of "Parity"
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It consists of one extra [[bit]] per [[byte]]/[[word]]. On storage or transmission, the parity bit is set so that the total number of 'on' bits across the entire group is either even (so-called 'even parity') or odd ('odd parity'). When the data is read back or received, the parity is checked, to make sure that it is what is expected. | It consists of one extra [[bit]] per [[byte]]/[[word]]. On storage or transmission, the parity bit is set so that the total number of 'on' bits across the entire group is either even (so-called 'even parity') or odd ('odd parity'). When the data is read back or received, the parity is checked, to make sure that it is what is expected. | ||
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| + | ==See also== | ||
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| + | * [[UNIBUS parity]] | ||
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| + | [[Category: Computer Basics]] | ||
Latest revision as of 15:31, 6 December 2020
Parity is a very early error-detectiion system (now mostly replaced by CRCs). It can detect all one-bit errors, but only about half of all two-bit errors.
It consists of one extra bit per byte/word. On storage or transmission, the parity bit is set so that the total number of 'on' bits across the entire group is either even (so-called 'even parity') or odd ('odd parity'). When the data is read back or received, the parity is checked, to make sure that it is what is expected.
