hd64338023s Renesas Electronics Corporation., hd64338023s Datasheet - Page 379

• Manufacturer Part Number: hd64338023s
• Description: Renesas 8-bit Single-chip Microcomputer Super Low Power Series
• Manufacturer: Renesas Electronics Corporation.

10.2.5
SMR is an 8-bit register used to set the serial data transfer format and to select the clock source for
the baud rate generator.
SMR can be read or written by the CPU at any time.
SMR is initialized to H'00 upon reset, and in standby, module standby, or watch mode.
Bit 7—Communication Mode (COM)
Bit 7 selects whether SCI3 operates in asynchronous mode or synchronous mode.
Bit 7
COM
0
1
Bit 6—Character Length (CHR)
Bit 6 selects either 7 or 8 bits as the data length to be used in asynchronous mode. In synchronous
mode the data length is always 8 bits, irrespective of the bit 6 setting.
Bit 6
CHR
0
1
Notes: 1. When 7-bit data is selected, the MSB (bit 7) of TDR is not transmitted.
Bit
Initial value
Read/Write
2. When 5-bit data is selected, set both PE and MP to 1. The three most significant bits
Serial Mode Register (SMR)
(bits 7, 6, and 5) of TDR are not transmitted.
Description
Asynchronous mode
Synchronous mode
Description
8-bit data/5-bit data *
7-bit data *
COM
R/W
7
0
1
/5-bit data *
CHR
R/W
6
0
2
2
R/W
PE
5
0
R/W
PM
4
0
Section 10 Serial Communication Interface
Rev. 7.00 Mar 10, 2005 page 337 of 652
STOP
R/W
3
0
R/W
MP
2
0
CKS1
R/W
REJ09B0042-0700
1
0
(initial value)
(initial value)
CKS0
R/W
0
0