Siemens SIMATIC CP 340 User Manual page 25

Character frame
Data is transmitted between the CP 340 and a communication partner via the serial interface
in a 10-bit or 11-bit character frame. Three data formats are available for each character
frame. You can assign parameters to the format you require using the CP 340: Point-to-Point
Communication, Parameter Assignment parameterization interface.
10-Bit Character Frame
The figure below shows the three possible data formats for an 10-bit character frame.
Figure 2-1
PtP coupling and configuration of CP 340
Manual, 04/2011, A5E00369892-03
1 2
1 2
1 2
10-Bit Character Frame
Basic Principles of Serial Data Transmission
2.1 Serial Transmission of a Character
8 9 10
8 9 10
9 10
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