8. Communication protocol
8.1. Introduction
This document describes the input and output command, information and data
of the SPM33 under MODBUS communication mode. So it is convenient for the
3
rd
part using and developing.
8.1.1 Purpose of the Communication Protocol
The purpose of the SPM33 MODBUS communications protocol is to allow setup
information and measured data to be efficiently transferred between a
MODBUS Master Station and SPM33. It includes:
1) Allowing setting and reading all SPM33 set-up parameters from a MODBUS
Master Station.
2) Allowing reading all data measured by a SPM33 and SOE (Event log).
8.1.2 Version of Communication Protocol
This document is proper for all versions of SPM33 meters. It will be declared, if
any change happens later.
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