H8SX1520R Datasheet, PDF (420/826 Pages) Renesas Technology Corp – 32-Bit CISC Microcomputer H8SX Family H8SX/1500 Series

Section 12 Serial Communication Interface (SCI)
12.3.4 Transmit Shift Register (TSR)
TSR is a shift register that transmits serial data. To perform serial data transmission, the SCI first
automatically transfers transmit data from TDR to TSR, then sends the data to the TxD pin. TSR
cannot be directly accessed by the CPU.
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.
• When SMIF in SCMR = 0
Bit
7
6
5
Bit Name
C/A
CHR
PE
Initial Value
0
0
0
R/W
R/W
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
• When SMIF in SCMR = 1
Bit
7
6
5
Bit Name
GM
BLK
PE
Initial Value
0
0
0
R/W
R/W
R/W
R/W
4
3
2
1
0
O/E
BCP1
BCP0
CKS1
CKS0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
Bit Functions in Normal Serial Communication Interface Mode (When SMIF in SCMR = 0):
Initial
Bit
Bit Name 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 (valid 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 (bit 7) in TDR is not transmitted in
transmission.
In clocked synchronous mode, a fixed data length of 8
bits is used.
Rev. 1.00 Mar. 06, 2006 Page 382 of 784
REJ09B0282-0100