Texas Instruments MSP430x4xx Family, Руководство пользователя

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USART Operation: UART Mode
17-15 USART Peripheral Interface, UART Mode
For example, the receive errors for the following conditions are calculated:
Baud rate = 2400
BRCLK =
32,768 Hz (ACLK)
UxBR = 13, since the ideal division factor is 13.65
UxMCTL = 6B:m7 = 0, m6 = 1, m5 = 1, m4 = 0, m3 = 1, m2 = 0, m1 = 1 and
m0 = 1 The LSB of UxMCTL is used first.
Data bit D1 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(2 UxBR
)
1)]
*
1
*
2
Ǔ
100%
+
0.29%
Data bit D2 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(3 UxBR
)
2)]
*
1
*
3
Ǔ
100%
+
2.83%
Data bit D3 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(4 UxBR
)
2)]
*
1
*
4
Ǔ
100%
+
−1.95%
Data bit D4 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(5 UxBR
)
3)]
*
1
*
5
Ǔ
100%
+
0.59%
Data bit D5 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(6 UxBR
)
4)]
*
1
*
6
Ǔ
100%
+
3.13%
Data bit D6 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(7 UxBR
)
4)]
*
1
*
7
Ǔ
100%
+
−1.66%
Data bit D7 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(8 UxBR
)
5)]
*
1
*
8
Ǔ
100%
+
0.88%
Parity bit Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(9 UxBR
)
6)]
*
1
*
9
Ǔ
100%
+
3.42%
Stop bit 1 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(10 UxBR
)
6)]
*
1
*
10
Ǔ
100%
+
−1.37%
Start bit Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(0 UxBR
)
0)]
*
1
*
0
Ǔ
100%
+
2.54%
Data bit D0 Error [%]
+
ǒ
baud rate
BRCLK
[2x(1
)
6)
)
(1 UxBR
)
1)]
*
1
*
1
Ǔ
100%
+
5.08%
The results show the maximum per-bit error to be 5.08% of a BITCLK period.