Slmp Frame Send Instruction; Precautions - Mitsubishi Electric FX5 User Manual

5.4

SLMP frame send instruction

Sending the SLMP frame
When sending a request message from the CPU module to the external device, use the following dedicated instructions.
Instruction symbol
SP.SLMPSND
Specify the external device and SLMP command to SP.SLMPSND instruction, execute SP.SLMPSND instruction in the
program, and the request message is sent from the CPU module to the external device. The response message from the
external device is stored to the device specified by SP.SLMPSND instruction.
CPU module
Ethernet
For details on SP.SLMPSND instruction, refer to MELSEC iQ-F FX5 Programming Manual (Instructions, Standard
Functions/Function Blocks)
5.5

Precautions

Checking communication status based on LED display
Check the status of the "SD/RD" LED display on the CPU module's built-in Ethernet port.
"SD/RD" LED indicator
status
Flashing
Off
The LED flashes brightly when performing SLMP (3E frame) communication normally.
If the LED is not flashing, check the wiring and the communication settings.
Checking communication status based on error code
For the error codes stored in the end code when there is an abnormal end of SLMP (3E frame) communication, refer to
Page 154 SLMP function error code.
5 SLMP FUNCTION
42
5.4 SLMP frame send instruction
Description
Sends SLMP messages to the SLMP-compatible device.
SP.SLMPSND instruction
Request message
Message format of SLMP
Header
Sub
Address
header
Message format of SLMP
Header
Sub
Address
header
Sent message
Operation status
Data is being sent or received.
Data is not being sent nor received.
Command
Data
Counterpart
device