WAGO 750-872/020-000 Manual page 262

254 • Application Examples
Visualization and control using SCADA software
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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