Table 18-12. Examples of UBRR Settings for Commonly Frequencies (Continued)
fclkio = 12.0000 MHz
U2X = 0 U2X = 1
UBRR UBRR
fclkio = 14.7456 MHz
U2X = 0 U2X = 1
UBRR UBRR
fclkio = 16.0000 MHz
U2X = 0 U2X = 1
UBRR UBRR
Baud
Rate
(bps)
Error
-0.2%
0.2%
0.2%
0.2%
0.2%
0.2%
-2.5%
0.2%
-2.7%
-8.9%
11.3%
0.0%
–
Error
0.0%
-0.2%
0.2%
0.2%
0.2%
0.2%
0.2%
0.2%
-2.5%
0.2%
-8.9%
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%
-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%
5.3%
-7.8%
-7.8%
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%
2400
4800
9600
14.4k
19.2k
28.8k
38.4k
57.6k
76.8k
115.2k
230.4k
250k
312
155
77
51
38
25
19
12
9
624
312
155
103
77
51
38
25
19
12
6
383
191
95
63
47
31
23
15
11
7
767
383
191
127
95
63
47
31
23
15
7
416
207
103
68
51
34
25
16
12
8
832
416
207
138
103
68
51
34
25
16
8
6
2
3
3
2
5
3
6
3
7
500k
–
2
1
3
1
3
1M
–
–
–
0
1
0
1
Max. (1)
750 kbps
UBRR = 0, Error = 0.0%
1.5 Mbps
921.6 kbps
1.8432 Mbps
1 Mbps
2 Mbps
1.
19. EUSART (Extended USART)
The Extended Universal Synchronous and Asynchronous serial Receiver and Transmitter
(EUSART) provides functionnal extensions to the USART.
19.1 Features
19.2 Overview
• Independant bit number configuration for transmit and receive
• Supports Serial Frames with 5, 6, 7, 8, 9 or 13, 14, 15, 16, 17 Data Bits and 1 or 2 Stop Bits
• Biphase Manchester encoder/decoder (for DALI Communications)
• Manchester framing error detection
• Bit ordering (MSB first or LSB first)
A simplified block diagram of the EUSART Transmitter is shown in Figure 19-1. CPU accessible
I/O Registers and I/O pins are shown in bold.
Figure 19-1. EUSART Block Diagram
The EUSART is activated with the EUSART bit of EUCSRB register. Until this bit is not set, the
USART will behave as standard USART, all the functionnalities of the EUSART are not
accessible.
The EUSART supports more serial frame formats than the standard USART interface:
210
AT90PWM2/3/2B/3B
4317J–AVR–08/10
ATMEL [ ATMEL ]
