h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 457

• Manufacturer Part Number: h8s-2158
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

16.3.9
BRR is an 8-bit register that adjusts the bit rate. As the SCI performs baud rate generator control
independently for each channel, different bit rates can be set for each channel. Table 16.2 shows
the relationships between the N setting in BRR and bit rate B for normal asynchronous mode and
clocked synchronous mode, and smart card interface mode. The initial value of BRR is H'FF, and
it can be read from or written to by the CPU at all times.
Table 16.2 Relationships between N Setting in BRR and Bit Rate B
Notes: B: Bit rate (bit/s)
Table 16.3 shows sample N settings in BRR in normal asynchronous mode. Table 16.4 shows the
maximum bit rate settable for each frequency. Table 16.6 shows sample N settings in BRR in
clocked synchronous mode, and table 16.8 shows sample N settings in BRR in smart card
interface mode. In smart card interface mode, the number of basic clock cycles S in a 1-bit data
transfer time can be selected. For details, see section 16.7.4, Receive Data Sampling Timing and
Reception Margin. Tables 16.5 and 16.7 show the maximum bit rates with external clock input.
Mode
Asynchronous
mode
Clocked
synchronous
mode
Smart card
interface mode
N: BRR setting for baud rate generator (0
n and S: Determined by the SMR settings shown in the following table.
: Operating frequency (MHz)
CKS1
0
0
1
1
Bit Rate Register (BRR)
SMR Setting
Bit Rate
B =
B =
B =
CKS0
0
1
0
1
64
S
8
2
2
2
2n – 1
2n + 1
2n – 1
Section 16 Serial Communication Interface (SCI, IrDA, and CRC)
10
10
10
(N + 1)
(N + 1)
6
(N + 1)
6
6
n
0
1
2
3
Error
Error (%) =
Error (%) =
—
N
255)
Rev. 3.00 Jan 25, 2006 page 405 of 872
BCP1
0
0
1
1
{
{
B
B
SMR Setting
64
S
2
2
2n + 1
2n – 1
BCP0
0
1
0
1
10
10
6
6
(N + 1)
(N + 1)
REJ09B0286-0300
– 1
– 1
S
32
64
372
256
}
}
100
100