Plcprogram.read - Siemens SIMATIC S7-1500 Function Manual

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3.20 API (Application Programming Interface)
3.20.5.3

PlcProgram.Read

The PlcProgram.Read method is used to read process data from the CPU.
To call the PlcProgram.Read method, you need the "read_value" authorization.
Structure of the request
The following table informs you about the properties of the tag to be read.
Name Required
"var" Yes
"mode" optional, default is
"simple"
Examples
In the following example, the user requests a global tag in the "simple" representation.
{
"var": "\"MotorSpeed\""
}
In the following example, the user requests a global tag in the "raw" representation.
{
"var": "\"MyDB\".MyVariable",
"mode": "raw"
}
Response structure
If the request to the server was successful, the server returns JSON data values.
Examples
The following example shows the result of reading a tag of type "int" in the "simple display".
-42
The following example shows the result of reading a tag of type "dword" in the "raw" display.
[ 1, 47, 233, 0 ]
176
Data type Description
String Name of the tag to be read
String Enumeration that determines the response format for this
method:
"simple": returns tag values according to the "simple"
•
representation in section "Supported data types
(Page 170)"
"raw": returns tag values according to the "raw" re-
•
presentation in section "Supported data types".
Function Manual, 11/2019, A5E03484625-AG
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