For "Send & Receive" Communication Type; When The Instruction Completed Successfully - Mitsubishi Electric MELSEC iQ-RJ71EN71 User Manual

For "Send & Receive" communication type
The packet is sent once. If the send completed successfully, the module shifts to the receiving standby state. When data is
received from the external device, it is verified with the receive packet (expected packet). If it matches, the receive processing
ends.
Ethernet-equipped module
Receive packet
(expected packet)
Data
The operation image of "Send & Receive" is shown below.

■When the instruction completed successfully

ECPRTCL instruction
Completion device
Completion device + 1
Ethernet-equipped module
External device
APPX
398
Appendix 10 Operation Image and Data Structure of Predefined Protocol
Not matched
Discarded
Matched
Received
Waiting time
to send
Send packet
Send packet
Send data
Data
Receive data 1
Header Data
Receive data 2
Header Data
Waiting time
to receive
Receive data
The receive data matched
the receive packet
(expected packet).
Receive data
Header
External device