Communication Structure; Data Communication Procedure - Mitsubishi Electric QJ71E71-100 User Manual

10.2

Communication Structure

When a connected device sends a message to an E71 in the SLMP message format, the E71 performs the process
according to the message. During communications, a CPU module including the E71 operates as a server, and the
connected device (a personal computer or other terminals) operates as a client. Based on the request message
received from the client, the server (the E71) automatically sends an appropriate response message.
Server
Ethernet
10.3

Data Communication Procedure

The following is a data communication procedure for SLMP communications.
1.
Set the parameters. (
2.
Perform the open process and establish a connection between the E71 and the connected device.
( Page 88, Section 7.2, Page 96, Section 7.3)
3.
Once the connection is established, the connected device sends an SLMP message.
4.
The connection is closed after the communications are completed.
In the cases described below, an E71 performs a remote password check when the connected device accesses the
programmable controller. If communications cannot be performed, unlock the remote password. (
14.4.2)
• When a remote password has been set in the CPU module
• When the connection for data communications with the connected device is to be subjected to the remote
password check
E71
Request message
Header Subheader
Header
Page 108, Section 10.4)
CHAPTER 10 SLMP COMMUNICATIONS
Connected device
Access
Command
destination
Response message
Subheader Response data
Client
Page 201, Section
107
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