AT32UC3B0512-A2UT Atmel, AT32UC3B0512-A2UT Datasheet - Page 303

• Manufacturer Part Number: AT32UC3B0512-A2UT
• Description: IC MCU AVR32 512K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR®32 UC3r

Specifications of AT32UC3B0512-A2UT

• Core Processor: AVR
• Core Size: 32-Bit
• Speed: 60MHz
• Connectivity: I²C, IrDA, SPI, SSC, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 44
• Program Memory Size: 512KB (512K x 8)
• Program Memory Type: FLASH
• Ram Size: 96K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Controller Family/series: AT32UC3B
• No. Of I/o's: 44
• Ram Memory Size: 96KB
• Cpu Speed: 60MHz
• No. Of Timers: 1
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

21.6.1.2
Table 21-3.
21.6.1.3
32059K–03/2011
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
3 686 400
4 915 200
5 000 000
7 372 800
8 000 000
MHz
Baud Rate Calculation Example
Fractional Baud Rate in Asynchronous Mode
Baud Rate Example (OVER = 0)
Expected Baud
Table 21-3
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%.
The Baud Rate generator previously defined is subject to the following limitation: the output fre-
quency changes by only integer multiples of the reference frequency. An approach to this
problem is to integrate a fractional N clock generator that has a high resolution. The generator
architecture is modified to obtain Baud Rate changes by a fraction of the reference source clock.
This fractional part is programmed with the FP field in the Baud Rate Generator Register
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
Error
BaudRate
shows calculations of CD to obtain a baud rate at 38400 bauds for different source
=
1
–
Calculation Result
⎛
⎝
ExpectedBaudRate
-------------------------------------------------- -
ActualBaudRate
=
(
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
CLKUSART
)
⎞
⎠
⁄
(
CD
CD
12
13
20
20
23
24
30
39
40
40
52
53
54
65
81
98
×
6
8
8
16
)
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
Bit/s
AT32UC3B
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%
Error
303