First I wanted to congratulate the author of an excellent program to operate the PLC and I think that he will continue to grow in the right direction. I hope you also will be added support for symbolic addressing for Siemens S71200.
Next what wonders why when moving the screen up and down are hidden all the indications and parameters taken from the PLC, also keys, values, indications, bars and sliders.? It is a solution, or is the bug in the application itself.?
This behavior is indeed ‘by design’. This is because at any given time the app is only polling the minimal amount of variables that still allow for a consistent interface. These are basically four kinds: variables that lay in the visible portion of the list; variables that need to be polled because they are used in expressions; variables that are configured as alarms; and variables that are being plotted on a graph.
With this approach, two different projects having 100 and 10000 variables may still have the same network overhead even if the total number of variables is significantly larger in the second case. Among other things this helps to give constant performance regardless of project size.
One consequence, is that we update the list of polled variables after the user stops scrolling up or down the interface. Before this happens, we chose to show blank space instead of possibly outdated data or indicators state, when actual (good) values from the PLC come in, they are displayed.
We may try in the future to update the list while it is being scrolled, as opposed to when it ended scrolling. This will improve the perceived lagging effect but still some delay must be expected due to the nature of the whole thing. We take this as a suggestion.
I hope this clears a bit how the app works internally.
It is possible to set the state of an input of the PLC as long as the button is pressed down, and after releasing reset.?
I use this function in WinCC Advenced to control the throttle position in manual mode.
It is already such a function in ScadaMobile? or it can add in features.
The normal behavior of push buttons in SM is to send 1 when pushed and to send 0 when released. In other words, any operation on a button implies two consecutive writes to the PLC. Of course, if you delay the release of the button, the sending of the 0 will be delayed too. If I understand you well, this is precisely what you want.
If you need to write an integer value depending on the button state then you must set the button on a INTERNAL tag and then use expressions on another tag accordingly to achieve whichever effect you want.