Supported Function Codes in MODBUS TCP

G

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gomathisankars

As per the MODBUS protocol specification version 1.1.b, some function codes are mentioned as Serial Only. Does this mean that these requests should not sent over TCP/UDP.

Following function codes are mentioned as Serial Only

07 (0x07) Read Exception Status (Serial Line only)
08 (0x08) Diagnostics (Serial Line only)
11 (0x0B) Get Comm Event Counter (Serial Line only)
12 (0x0C) Get Comm Event Log (Serial Line only)

Does this mean that these requests should not be in wrapped in Modbus TCP/UDP packet?
 
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