SAM3X8E Atmel Corporation, SAM3X8E Datasheet - Page 783

• Manufacturer Part Number: SAM3X8E
• Manufacturer: Atmel Corporation

Table 35-5.
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
Baud Rate Calculation Example
Source Clock
12 000 000
12 288 000
14 318 180
14 745 600
18 432 000
24 000 000
24 576 000
25 000 000
32 000 000
32 768 000
33 000 000
40 000 000
50 000 000
60 000 000
70 000 000
3 686 400
4 915 200
5 000 000
7 372 800
8 000 000
MHz
Baud Rate Example (OVER = 0)
Expected Baud
This gives a maximum baud rate of MCK divided by 8, assuming that MCK is the highest possi-
ble clock and that OVER is programmed to 1.
Table 35-5
clock frequencies. This table also shows the actual resulting baud rate and the error.
The baud rate is calculated with the following formula:
The baud rate error is calculated with the following formula. It is not recommended to work with
an error higher than 5%.
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
38 400
Rate
Bit/s
BaudRate
Baudrate
Error
shows calculations of CD to obtain a baud rate at 38400 bauds for different source
=
1
=
–
Calculation Result
=
--------------------------------------------
8 2 Over
ExpectedBaudRate
-------------------------------------------------- -
SelectedClock
MCK
ActualBaudRate
113.93
–
12.00
13.02
19.53
20.00
23.30
24.00
30.00
39.06
40.00
40.69
52.08
53.33
53.71
65.10
81.38
97.66
6.00
8.00
8.14
CD
CD
16
114
CD
12
13
20
20
23
24
30
39
40
40
52
53
54
65
81
98
6
8
8
Actual Baud Rate
38 400.00
38 400.00
39 062.50
38 400.00
38 461.54
37 500.00
38 400.00
38 908.10
38 400.00
38 400.00
38 461.54
38 400.00
38 109.76
38 461.54
38 641.51
38 194.44
38 461.54
38 580.25
38 265.31
38 377.19
Bit/s
SAM3X/A
SAM3X/A
0.00%
0.00%
1.70%
0.00%
0.16%
2.40%
0.00%
1.31%
0.00%
0.00%
0.16%
0.00%
0.76%
0.16%
0.63%
0.54%
0.16%
0.47%
0.35%
0.06%
Error
783
783