Character Frame; A.2.2 Character Frame - Siemens SENTRON PAC3100 Manual

Appendix
A.2 Modbus RTU
A.2.2

Character frame

The MODBUS RTU specification defines the data format. The user can change the data
format.
Structure of the character frame
The data is transferred between the SENTRON PAC Power Monitoring Device and the
MODBUS master via the serial interface in an 11-bit character frame. In exceptional cases,
only 10 bits are used.
Figure A-1
Figure A-2
The least significant bit (LSB) is sent at the start of the eight data bits, and the most
significant bit (MSB) is sent at the end.
126
11-bit character frame
10-bit character frame
SENTRON PAC3100
Manual, 07/2009, A5E02385159B-01