Access Range; Concept Of Control Procedure Of Slmp - Mitsubishi Electric MELSEC iQ-F Series FX5 User Manual

Access range

Ethernet communication frame
■When the external device is connected directly with the CPU module via Ethernet
In the following system configuration, communication with the CPU module is possible using the Ethernet communication
frame from the external device.
External device
Assigned symbol
A
2.3

Concept of Control Procedure of SLMP

This section describes the concept of the procedure (control procedure) when the external equipment accesses a CPU
module with SLMP.
Sending a command message
Data communication using SLMP communication is executed in half-duplex communication.
To access the CPU module, send the next command message after receiving a response message for the preceding
command message from the CPU module.
(Until the receiving of the response message is completed, the next command message cannot be sent.)
External equipment
PLC CPU
When a response message of completion for a command message cannot be received
■When a response message of completion with an error is received
Take corrective actions depending on the error code in the response message.
■When a response message or all messages cannot be received
Resend a command message after the monitoring time of the response monitoring timer elapses.
Change the set value of the monitoring time as needed.
2 SLMP DATA COMMUNICATION
12
2.3 Concept of Control Procedure of SLMP
Connecting station
A
A
A
Ethernet
Description
Station directly connected to the external device
(Command
message)
(Response
message)
(Command
message)
(Response
message)