Configuring Explicit Messaging Using DATA_EXCH
Original instructions
Overview
Use the DATA_EXCH function block to configure both Modbus TCP explicit messages and connected and unconnected EtherNet/IP explicit messages.
The Management_Param, the Data_to_Send, and the Received_Data parameters define the operation.
EN and ENO can be configured as additional parameters.
FBD Representation
Input Parameters
Parameter
Data type
Description
EN
BOOL
This parameter is optional. When this input is set to one, the block is activated and can solve the function blocks algorithm. When this input is set to zero, the block is deactivated and won’t solve the function block algorithm.
Address
Array [0...7] of INT
The path to the destination device, the content of which can vary depending on the message protocol. Use the Address function as an is input to the block parameter ADR.. Refer to a description of the Address parameter for:
ActionType
INT
The type of action to perform. For both the EtherNet/IP and Modbus TCP protocols, this setting = 1 (transmission followed by await reception).
Data_to_Send
Array [n...m] of INT
The content of this parameter is specific to the protocol, either EtherNet/IP or Modbus TCP.
For EtherNet/IP explicit messaging, refer to the topic Configuring the Data_To_Send Parameter.
For Modbus TCP explicit messaging, refer to Control Expert online help.
Input/Output Parameters
The Management_Param array is local:
Parameter
Data type
Description
Management_Param
Array [0...3] of INT
The management parameter, consisting of four words.
Do not copy this array during a switchover from a primary to a standby CPU in a Hot Standby system. Uncheck the Exchange On STBY variable in Control Expert when you configure a Hot Standby system.
NOTE: Refer to the description of Hot Standby system data management and the T_M_ECPU_HSBY DDT in the M580 Hot Standby System Planning Guide.
Output Parameters
Parameter
Data type
Description
ENO
BOOL
This parameter is optional. When you select this output you also get the EN input. ENO output is activated upon successful execution of the function block.
Received_Data
Array [n...m] of INT
The structure and content depends upon the specific protocol.