Specifications

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APPENDIX D: Asynchronous Communication
Figure D-1. Asynchronous communication bit diagram.
This special bit is called the parity bit. Parity is a simple
method of determining if a data bit has been lost or
corrupted during transmission. There are several
methods for implementing a parity check to guard
against data corruption. Common methods are called
(E)ven Parity or (O)dd Parity. Sometimes parity is not
used to detect errors on the data stream. This is referred
to as (N)o parity. Because each bit in asynchronous
communication is sent consecutively, it is easy to
generalize asynchronous communication by stating that
each character is wrapped (framed) by pre-defined bits
to mark the beginning and end of the serial
transmission of the character. The data rate and
communication parameters for asynchronous
communication have to be the same at both the