Schneider Electric LUFP9 Configuring the Content of the Query Frame, Field Size Description Frame

6. Configuring the Gateway

6.11.2.4. Configuring the Content of the Query Frame

The window shown below is obtained using “Edit Frame” from the “Query” menu. Unlike the tree structure in the main AbcConf window, this display has the advantage of showing all of the frame’s fields at the same time as well as their values. The values displayed below correspond to the values assigned by default to the Modbus command query we have created. The correspondence with the content of the corresponding Modbus frame has been added underneath this window.

Slave no.

Function no.

Word number (MSB / LSB)

Value of the word (MSB / LSB)

CRC16 (LSB / MSB)

Edit the values which are not greyed out, one after another. There is a description of them below.

The nature of a frame’s fields depends on the Modbus command to which it corresponds. However, a certain number of these fields are common to all frames, whereas others are common to a number of them. Here is a description of those shown above, for the example described at the beginning of the chapter 6.11.2:

Field in the	Size in the	Description
frame	frame
Slave	1 byte	This field cannot be changed by the user and its value is greyed out to inform
Address		him of the fact. AbcConf updates the value of this field automatically using the
		address of the Modbus slave corresponding to the current node.
		N.B. This field is common to queries for all Modbus commands.
		E.g. The value of this field is set to the address of the Modbus slave which
		corresponds to the “ATS48” node, that is to say 16#0A.
Function	1 byte	This field cannot be changed by the user and its value is greyed out to inform
		him of the fact. AbcConf updates the value of this field automatically using the
		function code for the corresponding Modbus command.
		N.B. This field is common to queries for all Modbus commands.
		E.g. The value of this field is set to the code for the “Preset Single Register”
		command (writing the value of an output word), that is to say 16#06.
Register	2 bytes	Address of an output word, or of a register, in the Modbus slave’s memory. So this
		field designates the memory object to which the command relates.
		N.B. This field is common to queries for all Modbus commands whose purpose
		is to access one or more locations in the memory of a Modbus slave. When
		accessing several memory locations, the “Register” field designates the
		address of the first word affected by the command.
		E.g. The value of this field should be changed by entering the address of the
		CMD command register, that is to say 400 (16#0190). This value will be
		automatically converted to hexadecimal if the user enters it in decimal.

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