387
Bit 5—Parity Enable (PE): In asynchronous mode, selects whether or not parity bit addition is
performed in transmission, and parity bit checking in reception. In synchronous mode, or when a
multiprocessor format is used, parity bit addition and checking is not performed, regardless of
the PE bit setting.
Bit 5
PE
Description
0
Parity bit addition and checking disabled
(Initial value)
1
Parity bit addition and checking enabled*
Note: * When the PE bit is set to 1, the parity (even or odd) specified by the O/
bit is added to
transmit data before transmission. In reception, the parity bit is checked for the parity
(even or odd) specified by the O/
bit.
Bit 4—Parity Mode (O/
): Selects either even or odd parity for use in parity addition and
checking.
The O/
bit setting is only valid when the PE bit is set to 1, enabling parity bit addition and
checking, in asynchronous mode. The O/
bit setting is invalid in synchronous mode, when
parity bit addition and checking is disabled in asynchronous mode, and when a multiprocessor
format is used.
Bit 4
O/
Description
0
Even parity*
1
(Initial value)
1
Odd parity*
2
Notes: 1. When even parity is set, parity bit addition is performed in transmission so that the
total number of 1 bits in the transmit character plus the parity bit is even.
In reception, a check is performed to see if the total number of 1 bits in the receive
character plus the parity bit is even.
2. When odd parity is set, parity bit addition is performed in transmission so that the total
number of 1 bits in the transmit character plus the parity bit is odd.
In reception, a check is performed to see if the total number of 1 bits in the receive
character plus the parity bit is odd.