Datasheet

Table Of Contents
Section 13 Serial Communication Interface
Page 388 of 846 REJ09B0140-0900 Rev. 9.00
Sep 16, 2010
H8S/2215 Group
13.3.5 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.