
178
2570N–AVR–05/11
ATmega325/3250/645/6450
Table 20-6.
Examples of UBRR Settings for Commonly Used Oscillator Frequencies (Continued)
Baud
Rate
(bps)
f
osc = 8.0000 MHz
f
osc = 11.0592 MHz
f
osc = 14.7456 MHz
U2Xn = 0U2Xn = 1
U2Xn = 0U2Xn = 1U2Xn = 0U2Xn = 1
UBRR
Error
UBRR
Error
UBRR
Error
UBRR
Error
UBRR
Error
UBRR
Error
2400
207
0.2%
416
-0.1%
287
0.0%
575
0.0%
383
0.0%
767
0.0%
4800
103
0.2%
207
0.2%
143
0.0%
287
0.0%
191
0.0%
383
0.0%
9600
51
0.2%
103
0.2%
71
0.0%
143
0.0%
95
0.0%
191
0.0%
14.4k
34
-0.8%68
0.6%
47
0.0%
95
0.0%
63
0.0%
127
0.0%
19.2k
25
0.2%
51
0.2%
35
0.0%
71
0.0%
47
0.0%
95
0.0%
28.8k16
2.1%
34
-0.8%
23
0.0%
47
0.0%
31
0.0%
63
0.0%
38.4k
12
0.2%
25
0.2%
17
0.0%
35
0.0%
23
0.0%
47
0.0%
57.6k
8
-3.5%
16
2.1%
11
0.0%
23
0.0%
15
0.0%
31
0.0%
76.8k6
-7.0%
12
0.2%
8
0.0%
17
0.0%
11
0.0%
23
0.0%
115.2k
3
8.5%
8
-3.5%
5
0.0%
11
0.0%
7
0.0%
15
0.0%
230.4k
1
8.5%
3
8.5%
2
0.0%
5
0.0%
3
0.0%
7
0.0%
250k
1
0.0%
3
0.0%
2-7.8%5-7.8%3
-7.8%6
5.3%
0.5M
0
0.0%
1
0.0%
––
2
-7.8%1
-7.8%3
-7.8%
1M
–
00.0%
–
–––
0
-7.8%1
-7.8%
Max. (1)
0.5 Mbps
1 Mbps
691.2 kbps
1.3824 Mbps
921.6 kbps
1.8432 Mbps
1.
UBRR = 0, Error = 0.0%