Datasheet

275
XMEGA B [DATASHEET]
8291B–AVR–01/2013
Figure 21-9. Fractional baud rate example.
Table 21-5. USART baud rate.
BSEL=0
BSCALE=0
f
BAUD
=f
PER
/8
clk
BAUD8
clk
BAUD8
BSEL=3
BSCALE=-6
f
BAUD
=f
PER
/8.375
clk
BAUD8
BSEL=3
BSCALE=-4
f
BAUD
=f
PER
/9.5
Extra clock cycle added
Baud f
OSC
= 32.0000MHz
rate
(bps)
CLK2X = 0 CLK2X = 1
BSEL BSCALE Error [%] BSEL BSCALE Error [%]
2400 12 6 0.2 12 7 0.2
4800 12 5 0.2 12 6 0.2
9600 12 4 0.2 12 5 0.2
14.4k
34 2 0.8 34 3 0.8
138 0 -0.1 138 1 -0.1
19.2k 12 3 0.2 12 4 0.2
28.8k
34 1 -0.8 34 2 -0.8
137 -1 -0.1 138 0 -0.1
38.4k 12 2 0.2 12 3 0.2
57.6k
34 0 -0.8 34 1 -0.8
135 -2 -0.1 137 -1 -0.1
76.8k 12 1 0.2 12 2 0.2
115.2k
33 -1 -0.8 34 0 -0.8
131 -3 -0.1 135 -2 -0.1
230.4k
31 -2 -0.8 33 -1 -0.8
123 -4 -0.1 131 -3 -0.1
460.8k
27 -3 -0.8 31 -2 -0.8
107 -5 -0.1 123 -4 -0.1