ATmega640/1280/1281/2560/2561
Table 22-10. Examples of UBRRn Settings for Commonly Used Oscillator Frequencies (Continued)
fosc = 3.6864 MHz fosc = 4.0000 MHz fosc = 7.3728 MHz
U2Xn = 0 U2Xn = 1 U2Xn = 0 U2Xn = 1 U2Xn = 0 U2Xn = 1
UBRR UBRR UBRR UBRR UBRR UBRR
Baud
Rate
(bps)
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%
-7.8%
-7.8%
–
Error
0.2%
0.2%
0.2%
2.1%
0.2%
-3.5%
-7.0%
8.5%
8.5%
8.5%
8.5%
0.0%
–
Error
0.2%
0.2%
0.2%
-0.8%
0.2%
2.1%
0.2%
-3.5%
-7.0%
8.5%
8.5%
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%
-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%
-7.8%
-7.8%
-7.8%
2400
4800
95
47
23
15
11
7
191
95
47
31
23
15
11
7
103
51
25
16
12
8
207
103
51
34
25
16
12
8
191
95
47
31
23
15
11
7
383
191
95
63
47
31
23
15
11
7
9600
14.4k
19.2k
28.8k
38.4k
57.6k
76.8k
115.2k
230.4k
250k
5
6
3
3
2
5
2
6
5
1
3
1
3
3
0
1
0
1
1
3
0
1
0
1
1
3
0.5M
–
0
–
0
0
1
1M
–
–
–
–
–
–
–
0
Max. (1)
230.4 kbps
UBRR = 0, Error = 0.0%
460.8 kbps
250 kbps
0.5 Mbps
460.8 kbps
921.6 kbps
1.
229
2549L–AVR–08/07
ATMEL [ ATMEL ]
