Hardware reference guide

Ethernet Modules
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Refer to the Quantum NOE 771 xx Ethernet Modules User Guide, 840USE11600 to
learn how to configure the MODBUS I/O Scanner.
MODBUS/TCP Server
The following information describes the functionality of the MODBUS/TCP Server.
Introduction –Client
All NOE771xx Quantum Ethernet TCP/IP modules provide the user with the
capability of transferring data to and from nodes on a TCP/IP network through the
use of a communication instruction. All PLCs that support networking
communication capabilities over Ethernet can use the MSTR Ladder Logic
instruction to read or write controller information or can also use IEC communication
blocks.
Introduction – Server
All NOE771xx Quantum Ethernet TCP/IP modules provide the user with the ability
to access data from the controller using the standard MODBUS/TCP protocol. Any
device: PC, HMI package, another PLC, or any MODBUS/TCP compliant device can
access data from the PLC. The MODBUS/TCP Server also allows programming
panels to log into the controller over Ethernet.
Limitations
The NOE771xx supports up to 64 simultaneous MODBUS/TCP Server connections.
The NOE771xx allows only one Programming Panel to be logged in at a time to
guarantee consistency of changes to the controller configuration.
The following MODBUS/TCP commands are supported by the NOE:
z Read Data
z Write Data
z Read/Write Data
z Get Remote Statistics
z Clear Remote Statistics
z MODBUS 125 Commands (used by programming panels to download a new
Exec to the NOE)
Input TimeOutState Individually Settable
IP Address Individually Settable
Remote Register Reference Configurable
Min. Update Rate Settable