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8-PORT SERIAL HOST ADAPTER PCI
An extra bit used for error detection is often appended before the stop bits.
This special bit is called the parity bit. Parity is a simple way to determine 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 called [N]o Parity). Because each bit in
asynchronous communication is sent consecutively, it 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 transmitting and receiving ends.
The communication parameters are baud rate, parity, number of data bits per
character, and stop bits—for example, 9600, N, 8, 1.
