RS485 então.
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M-BUS COMMUNICATION
PROTOCOL
Version 2 Revision 0
October 28th, 2008
Index
1.1 Introduction .......................................................................3
1.2 M-BUS functions ................................................................................................3
1.2.1 Single control character procedure SND_NKE................................................................3
1.2.2 Request/Respond Procedure (REQ/RSP)......................................................................3
1.2.3 Reset Function .........................................................................................5
1.2.4 Switching Baudrate Function ........................................................................................6
1.2.5 Primary Data Request (SND_UD)...........................................................................6
1.2.6 Special Addresses ...........................................................................................7
2 TABLES..............................................................................7
1.1 Introduction
The RS485 serial interface supports the M-BUS protocol. In this document only the
information necessary to read Data Measurement from EM21-EM24 has been reported
(not all the parts of the protocol have been implemented). ...
http://www.support-carlogavazzi.se/down ... otocol.pdf
Abraço
DJ