ModbusTcpNetwork

This component manages a TCP/IP network. In the property sheet of the ModbusTcpNetwork, you review the default global values for Modbus device data (the network automatically binds to the local TCP/IP address of the controller).
Figure 26.   ModbusTcpNetwork property sheet
Image

The ModbusTcpNetwork has the standard collection of network components, such as for status, health, monitor, tuning policies, and poll scheduler.

Other ModbusTcpNetwork properties such as Retry Count, Response Timeout, and Max Fails Until Device Down are typically left at defaults, unless particular reasons dictate the change.

You access local device properties by expanding Drivers > ModbusTcpNetwork in the Nav tree and double-clicking the ModbusTcpNetwork.

Property Value Description
Float Byte Order drop-down list Specifies the byte-order used to assemble or receive floating-point (32-bit) values in messages. Choices reflect two alternate methods, where numerals 0, 1, 2, and 3 represent the least significant byte to most significant byte:
  • Order3210 – Most significant byte first, or big-endian, it is the default.
  • Order1032 – Bytes transmitted in a 1,0,3,2 order, or little–endian.
Long Byte Order drop-down list

Specifies the byte-order used to assemble or receive long integer (32-bit) values in messages. Choices reflect two alternate methods, where numerals 0, 1, 2, and 3 represent the least significant byte to most significant byte:

  • Order3210 - Most significant byte first, or big-endian, it is the default.
  • Order1032 - Bytes transmitted in a 1,0,3,2 order, or little-endian.

 NOTE: Float or long values received in incorrect byte order may appear abnormally big, or not at all. 
Use Force Multiple Coil true or false (default) Specifies whether to use function code 15 (Force Multiple Coils) instead of function code 05 (Force Single Coil) when writing to coils. The default is false, where function code 05 (Force Single Coil) is used. This property depends on the Modbus function codes supported by child devices, which (if available) provide alternative options in Modbus messaging.

Function code 15 support (Preset Multiple Coils) is available in devices (true or false). The default is false, where function code Preset Single Coil is in place.

Use Preset Multiple Register true or false (default) Specifies whether to use function code 16 (Preset Multiple Registers) instead of function code 06 (Preset Single Register) when writing to registers. The default is false, where function code 06 (Preset Single Register) is used. This property depends on the Modbus function codes supported by child devices, which (if available) provide alternative options in Modbus messaging.

Function code 16 support (Preset Multiple Registers) is available in devices (true or false). The default is false, where function code Preset Single Register is in place.