3806_03 Datasheet, PDF (107/223 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.3 Serial I/O
Table 2.3.1 shows setting examples of Baud rate generator (BRG) values and transfer bit rate values,
Figure 2.3.38 shows a setting of related registers at a transmitting side, and Figure 2.3.39 shows a
setting of related registers at a receiving side.
Table 2.3.1 Setting examples of Baud rate generator values and transfer bit rate values
Transfer bit BRG count at f(XIN) = 4.9152 MHZ
at f(XIN) = 7.3728 MHZ
at f(XIN) = 8 MHZ
rate(bps) source
(Note 1) (Note 2) BRG setting value Actual time (bps) BRG setting value Actual time (bps) BRG setting value Actual time (bps)
600 f(XIN)/4 127(7F16)
600.00
191(BF16)
600.00 207(CF16)
600.96
1200 f(XIN)/4
63(3F16)
1200.00
95(5F16)
1200.00 103(6716)
1201.92
2400 f(XIN)/4
31(1F16)
2400.00
47(2F16)
2400.00
51(3316)
2403.85
4800 f(XIN)/4
15(0F16)
4800.00
23(1716)
4800.00
25(1916)
4807.69
9600 f(XIN)/4
7(0716)
9600.00
11(0B16)
9600.00
12(0C16)
9615.38
19200 f(XIN)/4
3(0316)
19200.00
5(0516) 19200.00
5(0516)
20833.33
38400 f(XIN)/4
1(0116)
38400.00
2(0216) 38400.00
2(0216)
41666.67
76800
f(XIN)
3(0316)
76800.00
5(0516) 76800.00
5(0516)
83333.33
31250
f(XIN)
15(0F16)
31250.00
62500
f(XIN)
7(0716)
62500.00
Notes 1: Equation of transfer bit rate
f(XIN)
Transfer bit rate (bps) =
(BRG setting value + 1) ! 16 ! m
m: when bit 0 of the Serial I/O1 control register (Address : 1A16) is set to “0,” a value
of m is 1.
when bit 0 of the Serial I/O1 control register (Address : 1A16) is set to “1,” a value
of m is 4.
2: A BRG count source is selected by bit 0 of the Serial I/O1 control register (Address : 1A16).
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3806 GROUP USER’S MANUAL