Cmsemicon CMS32L051 - Page 431

V1.2.2
CMS32L051 User Manual |Chapter 12 Universal Serial Communication Unit
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(2) Baud rate error at the time of sending
The baud rate error of UART (UART0~UART2) communication can be calculated using the following
calculation formula, and the baud rate of the sender must be set within the Enable range of the receiver's baud
rate.
An example of setting the UART baud rate at f
CLK
=32MHz is shown below.
UART baud rate
(Target baud rate)
f
CLK
=32MHz
Running clock (f
MCK
)
SDRmn[15:9]
Calculated value of the
baud rate
Error with target baud
rate
300bps
f
CLK
/2
9
103
300.48bps
+0.16%
600bps
f
CLK
/2
8
103
600.96bps
+0.16%
1200bps
f
CLK
/2
7
103
1201.92bps
+0.16%
2400bps
f
CLK
/2
6
103
2403.85bps
+0.16%
4800bps
f
CLK
/2
5
103
4807.69bps
+0.16%
9600bps
f
CLK
/2
4
103
9615.38bps
+0.16%
19200bps
f
CLK
/2
3
103
19230.8bps
+0.16%
31250bps
f
CLK
/2
3
63
31250.0bps
±0.0%
38400bps
f
CLK
/2
2
103
38461.5bps
+0.16%
76800bps
f
CLK
/2
103
76923.1bps
+0.16%
153600bps
f
CLK
103
153846bps
+0.16%
312500bps
f
CLK
50
313725bps
±0.39%
Remark m: Unit number (m=0, 1) n: Channel number (n=0, 2) mn=00, 02, 10.
(Baud rate error) = (calculated value of baud rate)  (value of target baud rate)  100–100[%].