r5f21368sdfp Renesas Electronics Corporation., r5f21368sdfp Datasheet - Page 449

• Manufacturer Part Number: r5f21368sdfp
• Description: Renesas Mcu R8c Family / R8c/3xt-a Series
• Manufacturer: Renesas Electronics Corporation.

Under development
R8C/36T-A Group
R01UH0240EJ0001 Rev.0.01
Apr 28, 2011
Figure 20.9
Table 20.8
Bit Rate
115200
14400
19200
28800
38400
57600
20.3.2.1
20.3.2.2
(bps)
1200
2400
4800
9600
In UART mode, the bit rate is the frequency divided by the U2BRG register divided by 16. Figure 20.9 shows
the Formula for Calculating U2BRG Register Setting Value and Table 20.8 lists the Bit Rate Setting Examples
in UART Mode (Internal Clock Selected).
If communication is aborted or a communication error occurs while transmitting or receiving in UART mode,
follow the procedures below:
(1) Set the TE bit in the U2C1 register to 0 (transmission disabled) and the RE bit to 0 (reception disabled).
(2) Set bits SMD2 to SMD0 in the U2MR register to 000b (serial interface disabled).
(3) Set bits SMD2 to SMD0 in the U2MR register to 100b (UART mode, transfer data 7 bits long), 101b
(4) Set the TE bit in the U2C1 register to 1 (transmission enabled) and the RE bit to 1 (reception enabled).
U2BRG
(UART mode, transfer data 8 bits long), or 110b (UART mode, transfer data 9 bits long).
Source
Count
f8
f8
f8
f1
f1
f1
f1
f1
f1
f1
Preliminary document
Specifications in this document are tentative and subject to change.
Bit Rate
Formula for Calculating U2BRG Register Setting Value
Bit Rate Setting Examples in UART Mode (Internal Clock Selected)
Measure for Dealing with Communication Errors
Set Value
129 (81h)
129 (81h)
42 (2Ah)
10 (0Ah)
64 (40h)
32 (20h)
86 (56h)
64 (40h)
32 (20h)
21 (15h)
U2BRG
System Clock = 20 MHz
• When an internal clock is selected
• When an external clock is selected
Value set in U2BRG register =
Value set in U2BRG register =
113636.36
fEXT: Count source frequency of U2BRG register (external clock)
14367.82
19230.77
29069.77
37878.79
56818.18
fj: Count source frequency of U2BRG register (f1, f8, f32, or fC1)
1201.92
2403.85
4734.85
9615.38
Actual
(bps)
Time
Setting
Error
-1.36
-0.22
-1.36
-1.36
-1.36
0.16
0.16
0.16
0.16
0.94
(%)
Set Value
119 (77h)
119 (77h)
29 (1Dh)
59 (3Bh)
79 (4Fh)
59 (3Bh)
29 (1Dh)
39 (27h)
19 (13h)
U2BRG
System Clock = 18.432 MHz
9 (09h)
115200.00
14400.00
19200.00
28800.00
38400.00
57600.00
2400.00
1200.00
4800.00
9600.00
Actual
(bps)
Time
Bit Rate ×16
Bit Rate ×16
fEXT
fj
Setting
Error
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
(%)
Set Value
12 (0Ch)
12 (0Ch)
51 (33h)
25 (19h)
51 (33h)
34 (22h)
25 (19h)
16 (10h)
- 1
- 1
U2BRG
8 (08h)
20. Serial Interface (UART2)
System Clock = 8 MHz
—
14285.71
19230.77
38461.54
55555.56
29411.76
1201.92
2403.85
4807.69
9615.38
Actual
(bps)
Time
Page 418 of 725
—
Setting
Error
-0.79
-3.55
0.16
0.16
0.16
0.16
0.16
2.12
0.16
(%)
—