Slmp; Outline - Mitsubishi Electric MR-JE-C Series Instruction Manual

2. CC-Link IE Field Network Basic/SLMP

2.4 SLMP

2.4.1 Outline

SLMP (SeamLess Message Protocol) is a common protocol which allows applications to communicate
seamlessly regardless of different types of networks and network layers. SLMP communications can be
performed for the connection with external devices, such as a programmable controller, a personal
computer, and HMI, that can send and receive messages by using SLMP control procedures. The MR-JE-
_C servo amplifier is compatible only with the binary code. It is not compatible with the ASCII code.
For the compatibility of SLMP with external devices, refer to manuals for external devices.
In SLMP, a command that a master station (external device) sends to slave stations (servo amplifiers) is
called a request message, and a command that the slave stations (servo amplifiers) send back to the master
station (external device) is called a response message.
When the servo amplifier receives the request message, it returns the response message to the external
device after the servo amplifier response time.
The external device cannot send the next request message until it completes receiving the response
message.
Master station (external device)
Slave station (servo amplifier)
Note. The servo amplifier response time differs depending on the command to send.
POINT
SLMP (UDP) is supported by servo amplifiers with software version A0 or later.
SLMP (TCP) is supported by servo amplifiers with software version A3 or later.
In SLMP (TCP), if connection with a client disconnects during establishment, the
connection may not close and this may cause reconnection failure. In case you
cannot reconnect, cycle the power of the servo amplifier.
When commands are sent from multiple master stations to a servo amplifier in
short intervals, the servo amplifier may fail to receive some of the commands.
When the servo amplifier does not respond to the commands, set longer
transmission interval. (For example, set the sending interval to approximately 10
ms when commands are periodically sent from two master stations.)
If the servo amplifier does not receive the commands, the following situations
may occur.
The monitor data of the servo amplifier is not updated in the master station.
The parameters of the servo amplifier are not changed in the master station.
Request
message
Servo amplifier response time (Note)
Response
message
2 - 7
Request
message
Response
message