6. Configuring the Gateway
6.11.2. With a Generic Modbus Slave
Unlike the previous chapter, here we will be looking at adding and setting up a Modbus command which is different from those configured by default with the LUFP7 gateway. We will benefit from this occasion to exhaustively describe the fields allowing you to set up the management of communications for a command of this sort.
Please see chapter 13 Appendix F: Modbus Commands, page 108, for a list of the Modbus functions supported by the LUFP7 gateway. If you need to use a command which is not supported by the gateway, you can configure one. A command of this sort is included in a specific element called “Transactions” or becomes a new Modbus command in its own right. Please see the next chapter, § 6.11.3 Adding a Special Modbus Command, page 80, for further details on this subject.
E.g. To illustrate the various operations to be carried out and the explanations given, we will be taking the example of a Altistart starter, the ATS48, and a Modbus command recognised both by the gateway and the ATS48. This is the “Preset Single Register” command, whose function code is 6 and which allows you to write the value of a unique output word. This function will be used to periodically write the value of the ATS48’s CMD command register, located at address W400 (address 400 = 16#0190).
Since the gateway’s default configuration already has 8 Modbus slaves, you will need to delete one of them, such as the “TeSys U n°2” node, for example, and to add a new node in its place (see chapter 6.6 Deleting a Modbus Slave, page 49, and chapter 6.7 Adding a Modbus Slave, page 50). Reminder: We strongly advise you not to delete the “TeSys U n°1” node, as it contains the commands corresponding to the read and write services for a parameter in a Modbus slave.
We rename the “New Node”, which has just been created, in “ATS48”, and we assign it the Modbus address 10, as shown here:
We then proceed to add the
“Preset Single Register” command by choosing “Add Command” from the “ATS48” menu.
In the window which appears (shown opposite), select the “0x06 Preset
Single Register” command and choose “Select” from the “File” menu.
Back in the main AbcConf window, the “Preset Single Register” command now appears in the list of Modbus commands for the “ATS48” node.
Expand the full tree structure for this command, shown at the top of the next page. The correspondence between the various elements which appear in this tree structure and the standard Modbus terminology is located to its right.
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