HMI Python module
- Last UpdatedOct 29, 2026
- 1 minute read
The HMI Extension Module allows users to call built-in language functions from a Python script. The built-in language functions of the HMI Extension Module are listed below, and the details of the Python implementation of each function follow this section.
Function attributes
There are some common characteristics for the Python implementation of these functions. See Function descriptions explained for more information on these characteristics.
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String expressions do not support VBScript or Python expressions, so that value in the function attributes tables is "No."
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Python is not supported on any viewer script (local Viewer, Mobile Access viewer, web Thin Clients), so the values in the Thin Clients and Mobile Access columns of function attributes tables are "Not Supported."
The function attributes table for the Python implementations of the these functions is:
|
Function |
Sync / Async Exec |
String Exp? |
Windows Support |
Windows Embedded Support |
IoT View Support |
Thin Client Support |
Mobile Access Support |
|---|---|---|---|---|---|---|---|
|
Function Name |
Synch or Asynch (see function) |
No |
Yes (see notes) |
Yes (see notes) |
Yes (see notes) |
No |
No |
The built-in function return values that indicate function failure can be captured in Python scripts, but failures due to incorrect parameters (number, type, etc.) will also generate Python runtime error messages that will halt Python script execution.
List of Available Functions
Log Message
Module Activity
System Info
Tags Database