Datasheet

V850ES/JG3 CHAPTER 15 ASYNCHRONOUS SERIAL INTERFACE A (UARTA)
R01UH0015EJ0300 Rev.3.00 Page 473 of 870
Sep 30, 2010
15.6.9 Parity types and operations
Caution When using the LIN function, fix the UAnPS1 and UAnPS0 bits of the UAnCTL0 register to 00.
The parity bit is used to detect bit errors in the communication data. Normally the same parity is used on the
transmission side and the reception side.
In the case of even parity and odd parity, it is possible to detect odd-count bit errors. In the case of 0 parity and no
parity, errors cannot be detected.
(a) Even parity
(i) During transmission
The number of bits whose value is “1” among the transmit data, including the parity bit, is controlled so as to be
an even number. The parity bit values are as follows.
• Odd number of bits whose value is “1” among transmit data: 1
• Even number of bits whose value is “1” among transmit data: 0
(ii) During reception
The number of bits whose value is “1” among the reception data, including the parity bit, is counted, and if it is
an odd number, a parity error is output.
(b) Odd parity
(i) During transmission
Opposite to even parity, the number of bits whose value is “1” among the transmit data, including the parity bit,
is controlled so that it is an odd number. The parity bit values are as follows.
• Odd number of bits whose value is “1” among transmit data: 0
• Even number of bits whose value is “1” among transmit data: 1
(ii) During reception
The number of bits whose value is “1” among the receive data, including the parity bit, is counted, and if it is an
even number, a parity error is output.
(c) 0 parity
During transmission, the parity bit is always made 0, regardless of the transmit data.
During reception, parity bit check is not performed. Therefore, no parity error occurs, regardless of whether the
parity bit is 0 or 1.
(d) No parity
No parity bit is added to the transmit data.
Reception is performed assuming that there is no parity bit. No parity error occurs since there is no parity bit.