r5f21368sdfp Renesas Electronics Corporation., r5f21368sdfp Datasheet - Page 420

• 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
Table 19.8
Note:
Bit Rate
115200
19.3.2.2
(bps)
14400
19200
28800
38400
57600
1. This applies when the high-speed on-chip oscillator is selected as the system clock and bits FRA22 to FRA20 in
1200
2400
4800
9600
In clock asynchronous serial I/O mode, the bit rate is obtained by dividing the frequency with the U0BRG
register and further dividing it by 16.
The value to be set in the U0BRG register is calculated as follows:
• When an internal clock is selected
• When an external clock is selected
the FRA2 register are set to 000b (divide-by-2 mode). For details on the accuracy of the high-speed on-chip
oscillator, refer to 28. Electrical Characteristics .
Value set in U0BRG register =
Value set in U0BRG register =
U0BRG
Source
Count
f8
f1
f1
f8
f8
f1
f1
f1
f1
f1
Preliminary document
Specifications in this document are tentative and subject to change.
Bit Rate
Setting Example for Clock Asynchronous Serial I/O Mode (Internal Clock Selected)
in U0BRG
Value Set
129 (81h)
129 (81h)
Register
42 (2Ah)
10 (0Ah) 113636.36
64 (40h)
32 (20h)
86 (56h)
64 (40h)
32 (20h)
21 (15h)
System Clock = 20 MHz
Rate (bps)
14367.82
19230.77
29069.77
37878.79
56818.18
Actual
1201.92
2403.85
4734.85
9615.38
Setting
fj: Frequency of U0BRG count source (f1, f8, f32, or fC1)
fEXT: Frequency of U0BRG count source (external clock)
Bit rate × 16
Bit rate × 16
Error
(%)
-1.36
-0.22
-1.36
-1.36
-1.36
0.16 119 (77h)
0.16
0.16 119 (77h)
0.16
0.94
fEXT
fj
System Clock = 18.432 MHz
in U0BRG
Value Set
Register
29 (1Dh)
59 (3Bh)
29 (1Dh)
59 (3Bh)
79 (4Fh)
39 (27h)
19 (13h)
9 (09h) 115200.00
- 1
- 1
Rate (bps)
14400.00
19200.00
28800.00
38400.00
57600.00
Actual
1200.00
2400.00
4800.00
9600.00
Setting
Error
(%)
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
(1)
in U0BRG
Value Set
Register
12 (0Ch)
12 (0Ch)
34 (22h)
25 (19h)
51 (33h)
25 (19h)
51 (33h)
16 (10h)
8 (08h)
19. Serial Interface (UART0)
System Clock = 8 MHz
—
Rate (bps)
38461.54
14285.71
19230.77
55555.56
29411.76
Actual
1201.92
2403.85
4807.69
9615.38
Page 389 of 725
—
Setting
Error
(%)
-0.79
-3.55
0.16
0.16
0.16
0.16
0.16
2.12
0.16
—