hd64338023s Renesas Electronics Corporation., hd64338023s Datasheet - Page 390

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

Section 10 Serial Communication Interface
10.2.8
BRR is an 8-bit register that designates the transmit/receive bit rate in accordance with the baud
rate generator operating clock selected by bits CKS1 and CKS0 of the serial mode register (SMR).
BRR can be read or written by the CPU at any time.
BRR is initialized to H'FF upon reset, and in standby, module standby, or watch mode.
Table 10.3 shows examples of BRR settings in asynchronous mode. The values shown are for
active (high-speed) mode.
Table 10.3 Examples of BRR Settings for Various Bit Rates (Asynchronous Mode) (1)
Bit Rate
(bit/s)
110
150
200
250
300
600
1200
2400
4800
9600
19200
31250
38400
Rev. 7.00 Mar 10, 2005 page 348 of 652
REJ09B0042-0700
Bit
Initial value
Read/Write
Bit Rate Register (BRR)
n
—
—
—
0
—
—
16.4 kHz
N
—
—
—
1
—
—
BRR7
R/W
7
1
Error
(%)
—
—
—
2.5
—
—
BRR6
n
—
0
0
—
0
0
—
—
—
—
—
—
—
R/W
6
1
19.2 kHz
N
—
3
2
—
1
0
—
—
—
—
—
—
—
BRR5
R/W
Error
(%)
—
0
0
—
0
0
—
—
—
—
—
—
—
5
1
n
2
2
2
3
0
0
0
0
—
—
—
0
—
BRR4
R/W
4
1
1 MHz
N
17
12
9
103 0.16
51
25
12
—
—
—
0
—
1
φ φ φ φ
Error
(%)
–1.36 2
0.16
–2.34 3
–2.34 0
0.16
0.16
0.16
—
—
—
0
—
BRR3
R/W
3
1
n
3
3
3
2
2
0
0
0
—
0
1.2288 MHz
BRR2
R/W
N
21
3
2
153 –0.26 2
1
0
1
0
7
3
1
—
0
2
1
Error
(%)
–0.83 3
0
0
0
0
0
0
0
0
0
—
0
BRR1
R/W
1
1
n
2
3
2
0
0
0
0
—
—
0
—
2 MHz
N
8
25
4
15
12
103 0.16
51
25
12
—
—
1
—
BRR0
R/W
0
1
Error
(%)
–1.36
0.16
–2.34
–2.34
0.16
0.16
0.16
0.16
—
—
0
—