TcModbusSrv

The defined modbus functions are implemented in the PLC library TcModbusSrv.lib.

Modbus TCP function	Function code	PLC block
Read Coils	1	FB_MBReadCoils
Read Discrete Inputs	2	FB_MBReadInputs
Read Registers	3	FB_MBReadRegs
Read Input Registers	4	FB_MBReadInputRegs
Write Single Coil	5	FB_MBWriteSingleCoil
Write Single Register	6	FB_MBWriteSingleReg
Write Multiple Coils	15	FB_MBWriteCoils
Write Multiple Registers	16	FB_MBWriteRegs
Read/Write Multiple Registers	23	FB_MBReadWriteRegs
Diagnostic	8	FB_MBDiagnose

Modbus UDP function	Function code	PLC block
Read Coils	1	FB_MBUdpReadCoils
Read Discrete Inputs	2	FB_MBUdpReadInputs
Read Registers	3	FB_MBUdpReadRegs
Read Input Registers	4	FB_MBUdpReadInputRegs
Write Single Coil	5	FB_MBUdpWriteSingleCoil
Write Single Register	6	FB_MBUdpWriteSingleReg
Write Multiple Coils	15	FB_MBUdpWriteCoils
Write Multiple Registers	16	FB_MBUdpWriteRegs
Read/Write Multiple Registers	23	FB_MBUdpReadWriteRegs
Diagnostic	8	FB_MBUdpDiagnose

Further Information