Negotiate Communication Specifications
This step introduces key points for negotiating communication specifications, including communication protocol selection, data format definition, and communication flow design. Based on actual conditions and requirements, refer to this section to negotiate with the communication counterpart and clarify specification details.
Supported Communication Protocols
Mech-MSR supports the following communication protocols. Select a protocol according to your actual scenario. For details, see Key Points for Negotiating Communication Specifications.
| Protocol Type | Role | Applicable Scenario |
|---|---|---|
TCP Server |
Server (listens for connections) |
Peer devices actively connect; production stations and upper-level control systems |
TCP Client |
Client (actively connects) |
Need to actively connect to an external server; remote integration scenarios |
Siemens S7 Client |
Client (connects to S7 PLC) |
Integration with Siemens S7 series PLCs |
Modbus TCP Slave |
Slave (responds to queries) |
Acts as a Modbus slave station to communicate with upper-level systems/PLCs |
Mitsubishi MC Client |
Client (connects to Mitsubishi PLC) |
Integration with Mitsubishi PLCs |
Key Points for Negotiating Communication Specifications
After determining the communication protocol, refer to the following content to negotiate specific specifications with the communication counterpart.
TCP Server
When the TCP Server protocol is used, Mech-MSR acts as the server and listens for connection requests from external devices. Make sure external devices can actively connect to the IP address and port of Mech-MSR.
Key points to negotiate when using the TCP Server protocol include:
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Determine the communication flow. For details, see Operating Mechanism of Custom Communication Mode.
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Determine the IP address and port assigned to Mech-MSR, and ensure they are accessible to external devices.
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Determine the data format of sent and received messages, either ASCII strings or hexadecimal data.
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If ASCII strings are used, clarify message terminators, separators, the meaning of each segment, and target parsed data types (numeric or string).
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If hexadecimal data is used, clarify message terminators and parsing rules for each field, including field meaning, start position, byte length, and target parsed data type (Char8, Int16, Int32, or Float32).
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Determine the formats and meanings of all sent and received messages in the communication flow. For example:
t,1\n
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Here,
trepresents the command type (user-trigger project type),1represents the command project ID, and\nrepresents the message terminator.
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TCP Client
When the TCP Client protocol is used, Mech-MSR acts as the client and actively connects to external devices. Make sure Mech-MSR can access the IP address and port of external devices.
Key points to negotiate when using the TCP Client protocol include:
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Determine the communication flow. For details, see Operating Mechanism of Custom Communication Mode.
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Determine the IP address and port of external devices (servers), and ensure network connectivity between both sides.
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Determine the data format of sent and received messages, either ASCII strings or hexadecimal data.
-
If ASCII strings are used, clarify message terminators, separators, the meaning of each segment, and target parsed data types (numeric or string).
-
If hexadecimal data is used, clarify message terminators and parsing rules for each field, including field meaning, start position, byte length, and target parsed data type (Char8, Int16, Int32, or Float32).
-
-
Determine the formats and meanings of all sent and received messages in the communication flow. For example:
t,1\n
-
Here,
trepresents the command type (user-trigger project type),1represents the command project ID, and\nrepresents the message terminator.
-
Siemens S7 Client
When the Siemens S7 Client protocol is used, Mech-MSR acts as the client and actively connects to Siemens S7 PLCs. Make sure Mech-MSR can access the IP address and port of the S7 PLC, and that the S7 PLC is configured correctly to allow connections.
Key points to negotiate when using the Siemens S7 Client protocol include:
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Determine the communication flow. For details, see Operating Mechanism of Custom Communication Mode.
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Determine the IP address and port of the S7 PLC, and ensure Mech-MSR can access them.
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Determine the S7 PLC data block (DB) to access, and define for each interaction signal in the communication flow: signal name and meaning, start register position and quantity occupied, data type, and read/write permissions.
For example, if the DB block is DB83 and the signal used in the communication flow is
heartbeat, then its meaning is heartbeat, its start register position is 0, its quantity is 1, its data type isbool, and its permission is read/write.If heartbeat checking is enabled when configuring a Siemens S7 Client custom service, Mech-MSR periodically alternately writes 0 and 1 to register 0 of DB83 to implement heartbeat.
Modbus TCP Slave
When the Modbus TCP Slave protocol is used, Mech-MSR acts as the slave and responds to query requests from external devices (masters). Make sure Mech-MSR can access the IP address and port of external devices.
Key points to negotiate when using the Modbus TCP Slave protocol include:
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Determine the communication flow. For details, see Operating Mechanism of Custom Communication Mode.
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Determine the IP address and port of external devices (masters), and ensure network connectivity between both sides.
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Determine the slave device address assigned to Mech-MSR. The default is 1.
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Determine byte order.
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Determine for each interaction signal in the communication flow: signal name and meaning, start register position and quantity occupied, data type, and read/write permissions.
Mitsubishi MC Client
When the Mitsubishi MC Client protocol is used, Mech-MSR acts as the client and actively connects to Mitsubishi PLCs. Make sure Mech-MSR can access the IP address and port of the Mitsubishi PLC, and that the PLC is configured correctly to allow connections.
Key points to negotiate when using the Mitsubishi MC Client protocol include:
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Determine the communication flow. For details, see Operating Mechanism of Custom Communication Mode.
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Determine the IP address, port, and communication frame of the Mitsubishi PLC, and ensure Mech-MSR can access them.
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Determine for each interaction signal in the communication flow: signal name and meaning, start register position and quantity occupied, data type, and read/write permissions.
After communication specification negotiation is complete, proceed to Configure Custom Communication Service.