Tab: System Events
Object: Task Configuration
On the System Events tab, you define which event calls which function and whether or not the configuration is currently activated. You use this tab when a "system event" (instead of a task) should call a project function.
Add Event Handler | Opens the Add Event Handler dialog |
Remove Event Handler | Deletes the selected list assignment |
Event Info | Shows information from the corresponding event library |
Open Event Function | Opens the editor of the new function for the selected assignment You have selected the implementation language of the new function in the Add Event Handler dialog. |
List of mappings of functions to call to events with: Name, Description, Function to call, and Active (enable or disable the configuration) |
Adds a new assignment "Event – Function to call" to the list | |
Event | The possible selection depends on the target device. CODESYS marks unavailable events with a red symbol in front of the name. A list of all possible system events is located at the end of this section. |
Function to call | Function name (POU, type FUNCTION) You need to specify the name of the new function. CODESYS inserts the function to the device tree after you confirm the dialog. |
Scope |
|
Implementation language | Implementation language for the new function |
Description | Short description of the selected event |
Features in Online Mode
The list of assignments from called functions to events also includes the following information: Event Status, Call Count, and the Online Reset button.
Event Status |
Does not equal |
Call Count | Displays how often the event has occurred or the associated function has been called |
Online Reset | CODESYS reinitializes the event lists and resets the counter for the events/function calls. Incorrectly initialized events are displayed with a red status line. |
Possible system events
Event | Description | Task | Debugging |
---|---|---|---|
| Call before starting the application | Communication task | No |
| Call after starting the application | Communication task | No |
| Call before stopping the application | Communication task | No |
| Call after stopping the application | Communication task | No |
| Call before resetting the application | Communication task | No |
| Call after resetting the application | Communication task | No |
| Call before online change of the application | Communication task | No |
| Call after online change of the application | Communication task | No |
| Call before downloading the application | Communication task | No |
| Call after downloading the application | Communication task | No |
| Call before deleting the application | Communication task | No |
| Call after deleting the application | Communication task | No |
| Call before exiting the application | Communication task | No |
| Call after exiting the application | Communication task | No |
| Event is sent after Code Init. Called within the Task Safe Section and only with an online change. (For example, the copy code for online change is executed here) | Communication task | No |
| The event is sent if an exception has occurred in the context of an application. | Exception handling task of the runtime, or the task itself if the runtime does not support exception handling | Depends on the task |
| Login of a client to this application | Communication task | No |
| Logout of a client from this application | Communication task | No |
| Call before reading the inputs | IEC task | Yes |
| Call after reading the inputs | IEC task | Yes |
| Call before writing the outputs | IEC task | Yes |
| Call after writing the outputs | IEC task | Yes |
| Event is sent in cycles to the debug loop if the IEC task stops at a breakpoint. | Communication task | No |
| Event is sent immediately before the runtime is downloaded. | Runtime main loop | No |
| Event is sent during download before exiting the communication server. | Runtime main loop | No |
| Event is sent during download before exiting ( | Runtime main loop | No |