WAGO 750 Series Manual page 160

154 • Application Examples
Example of the MODBUS function code
In the case of SCADA Software Lookout from National Instruments the
MODBUS function codes are used with a 6 bit coding, whereby the first bit
represents the function code:
Input code: MODBUS function code
The following five digits specify the channel number of the consecutively
numbered digital or analog input and/or output channels.
Examples:
- Read the first digital input:
- Read the second analog input:
Application example:
Thus, the digital input channel 2 of the above node "Measuring data" can be
read out with the input: "Measuring data. 0 0000 2".
Fig. 6-1: Example of user software
More information
Please refer to the respective SCADA product manual for a detailed
description of the particular software operation.
0 FC1 read coils
1 FC2 read input discretes
3 FC3 read multiple registers
4 FC4 read input registers
Reading of several input bits
Reading of several input bits
Reading of several input registers
Reading of an individual input register
i.e. 0 0000 1
i.e. 3 0000 2
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