ATmega8(L)
Table 63. Examples of UBRR Settings for Commonly Used Oscillator Frequencies (Continued)
fosc = 16.0000 MHz fosc = 18.4320 MHz
U2X = 0 U2X = 1 U2X = 0 U2X = 1
UBRR UBRR UBRR UBRR
fosc = 20.0000 MHz
Baud
Rate
(bps)
U2X = 0
U2X = 1
UBRR
Error
-0.1%
0.2%
0.2%
0.6%
0.2%
-0.8%
0.2%
2.1%
0.2%
-3.5%
8.5%
0.0%
0.0%
0.0%
Error
0.0%
-0.1%
0.2%
-0.1%
0.2%
0.6%
0.2%
-0.8%
0.2%
2.1%
-3.5%
0.0%
0.0%
0.0%
Error
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
-7.8%
–
Error
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
0.0%
2.4%
-7.8%
–
UBRR
520
259
129
86
64
42
32
21
15
10
4
Error
0.0%
0.2%
0.2%
-0.2%
0.2%
0.9%
-1.4%
-1.4%
1.7%
-1.4%
8.5%
0.0%
–
Error
0.0%
0.0%
0.2%
-0.2%
0.2%
-0.2%
0.2%
0.9%
-1.4%
-1.4%
-1.4%
0.0%
0.0%
–
2400
4800
9600
14.4k
19.2k
28.8k
38.4k
57.6k
76.8k
115.2k
230.4k
250k
416
207
103
68
51
34
25
16
12
8
832
416
207
138
103
68
51
34
25
16
8
479
239
119
79
59
39
29
19
14
9
959
479
239
159
119
79
59
39
29
19
9
1041
520
259
173
129
86
64
42
32
21
3
4
10
3
7
4
8
4
9
0.5M
1M
1
3
–
4
–
4
0
1
–
–
–
–
–
–
Max (1)
1 Mbps
UBRR = 0, Error = 0.0%
2 Mbps
1.152 Mbps
2.304 Mbps
1.25 Mbps
2.5 Mbps
1.
159
2486M–AVR–12/03
ATMEL [ ATMEL ]
