Datasheet

Section 12 Serial Communication Interface
Rev.7.00 Dec. 24, 2008 Page 369 of 698
REJ09B0074-0700
12.3.5 Serial Mode Register (SMR)
SMR is used to set the SCI's serial transfer format and select the baud rate generator clock source.
Some bits in SMR have different functions in normal mode and smart card interface mode.
• Normal Serial Communication Interface Mode (When SMIF in SCMR is 0)
Bit Bit Name Initial Value R/W Description
7 C/A 0 R/W Communication Mode
0: Asynchronous mode
1: Clocked synchronous mode
6 CHR 0 R/W Character Length (enabled only in asynchronous mode)
0: Selects 8 bits as the data length
1: Selects 7 bits as the data length. LSB-first is fixed
and the MSB of TDR is not transmitted in
transmission
In clocked synchronous mode, a fixed data length of 8
bits is used.
5 PE 0 R/W Parity Enable (enabled only in asynchronous mode)
When this bit is set to 1, the parity bit is added to
transmit data before transmission, and the parity bit is
checked in reception. For a multiprocessor format, parity
bit addition and checking are not performed regardless
of the PE bit setting.
4 O/E 0 R/W Parity Mode (enabled only when the PE bit is 1 in
asynchronous mode)
0: Selects even parity
1: Selects odd parity
3 STOP 0 R/W Stop Bit Length (enabled only in asynchronous mode)
Selects the stop bit length in transmission.
0: 1 stop bit
1: 2 stop bits
In reception, only the first stop bit is checked. If the
second stop bit is 0, it is treated as the start bit of the
next transmit character.