HD64F2638F20J Datasheet, PDF (502/1512 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

Section 13 Serial Communication Interface (SCI)
H8S/2639, H8S/2638, H8S/2636,
H8S/2630, H8S/2635 Group
13.2.5 Serial Mode Register (SMR)
Bit
:
Initial value :
R/W
:
7
C/A
0
R/W
6
5
CHR
PE
0
0
R/W R/W
4
3
2
1
0
O/E STOP MP CKS1 CKS0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
SMR is an 8-bit register used to set the SCI’s serial transfer format and select the baud rate
generator clock source.
SMR can be read or written to by the CPU at all times.
SMR is initialized to H'00 by a reset and in hardware standby mode.
Bit 7—Communication Mode (C/A): Selects asynchronous mode or clocked synchronous mode
as the SCI operating mode.
Bit 7
C/A
0
1
Description
Asynchronous mode
Clocked synchronous mode
(Initial value)
Bit 6—Character Length (CHR): Selects 7 or 8 bits as the data length in asynchronous mode. In
clocked synchronous mode, a fixed data length of 8 bits is used regardless of the CHR setting.
Bit 6
CHR
Description
0
8-bit data
1
7-bit data^*
(Initial value)
Note: * When 7-bit data is selected, the MSB (bit 7) of TDR is not transmitted, and it is not possible
to choose between LSB-first or MSB-first transfer.
Page 452 of 1458
REJ09B0103-0800 Rev. 8.00
May 28, 2010