Datasheet

211
4317K–AVR–03/2013
AT90PWM2/3/2B/3B
Table 18-12. Examples of UBRR Settings for Commonly Frequencies (Continued)
Baud
Rate
(bps)
fclk
io
= 12.0000 MHz fclk
io
= 14.7456 MHz fclk
io
= 16.0000 MHz
U2X = 0 U2X = 1 U2X = 0 U2X = 1 U2X = 0 U2X = 1
UBRR Error UBRR Error UBRR Error UBRR Error UBRR Error UBRR Error
2400 312 -0.2% 624 0.0% 383 0.0% 767 0.0% 416 -0.1% 832 0.0%
4800 155 0.2% 312 -0.2% 191 0.0% 383 0.0% 207 0.2% 416 -0.1%
9600 77 0.2% 155 0.2% 95 0.0% 191 0.0% 103 0.2% 207 0.2%
14.4k 51 0.2% 103 0.2% 63 0.0% 127 0.0% 68 0.6% 138 -0.1%
19.2k 38 0.2% 77 0.2% 47 0.0% 95 0.0% 51 0.2% 103 0.2%
28.8k 25 0.2% 51 0.2% 31 0.0% 63 0.0% 34 -0.8% 68 0.6%
38.4k 19 -2.5% 38 0.2% 23 0.0% 47 0.0% 25 0.2% 51 0.2%
57.6k 12 0.2% 25 0.2% 15 0.0% 31 0.0% 16 2.1% 34 -0.8%
76.8k 9 -2.7% 19 -2.5% 11 0.0% 23 0.0% 12 0.2% 25 0.2%
115.2k 6 -8.9% 12 0.2% 7 0.0% 15 0.0% 8 -3.5% 16 2.1%
230.4k 2 11.3% 6 -8.9% 3 0.0% 7 0.0% 3 8.5% 8 -3.5%
250k 2 0.0% 5 0.0% 3 -7.8% 6 5.3% 3 0.0% 7 0.0%
500k – – 2 0.0% 1 -7.8% 3 -7.8% 1 0.0% 3 0.0%
1M – – – – 0 -7.8% 1 -7.8% 0 0.0% 1 0.0%
Max.
(1)
750 kbps 1.5 Mbps 921.6 kbps 1.8432 Mbps 1 Mbps 2 Mbps
1. UBRR = 0, Error = 0.0%