History
Early computers sometimes required the use of parity RAM, and parity-checking could not be disabled. A parity error typically caused the machine to halt, with loss of unsaved data; this is usually a better option than saving corrupt data. Logic parity RAM, also known as fake parity RAM, is non-parity RAM that can be used in computers that require parity RAM. Logic parity RAM recalculates an always-valid parity bit each time a byte is read from memory, instead of storing the parity bit when the memory is written to; the calculated parity bit, which will not reveal if the data has been corrupted (hence the name "fake parity"), is presented to the parity-checking logic. It is a means of using cheaper 8-bit RAM in a system designed to use only 9-bit parity RAM.
Read more about this topic: RAM Parity
Famous quotes containing the word history:
“No event in American history is more misunderstood than the Vietnam War. It was misreported then, and it is misremembered now.”
—Richard M. Nixon (b. 1913)
“It takes a great deal of history to produce a little literature.”
—Henry James (18431916)
“The history of medicine is the history of the unusual.”
—Robert M. Fresco, and Jack Arnold. Prof. Gerald Deemer (Leo G. Carroll)