Schneider Optics Web Embedded Server - Manual (Page 35)

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3
The MSTR Instruction
3.1 Introduction
All NOE 2X1 10 Quantum Ethernet web embedded server modules provide the
user with the capability of transferring data to and from nodes on a Modbus Plus or
TCP/IP network through the use of a special MSTR (master instruction). All PLCs
that support networking communication capabilities over Modbus Plus and
Ethernet can use the MSTR ladder logic instruction to read or write controller
information.
3.2 MSTR Description
The MSTR instruction allows you to initiate one of 12 possible network
communications operations over the network. Each operation is designated by a
code. The following table lists the 12 operations and indicates those that are
supported on an Ethernet TCP/IP network.
MSTR Operation Code TCP/IP Ethernet Support
Write data 1 supported
Read Data 2 supported
Get local statistics 3 supported
Clear local statistics 4 supported