Buttons Not Working in WinCC Unified

[aamirawan91]

I am creating a project with WinCC Unified v16 Upd6 (PC runtime) with an S7-1200. The communication is good between the PC and the PLC as I can see the correct values on my IO field. The indication lights are also working properly, but the buttons on my screen that are linked to PLC tags are not working. Buttons that are used to change screens are working as they are not linked to PLC tags. There is no communication issue; I am sure of that. If there was any communication issue, the lights and the IO fields would not work properly. Tags are properly addressed. I have double-checked that too. I configured the button this way:

Events > Press > SetBitInTag

Tag: Start conveyor

Value: 0

Then I changed the value to 1 but that didn't work either. What am i doing wrong? I have also attached the button properties snap.

 

[drbitboy]

Is the SetBitInTag function meant for a boolean tag, or is it for an integer tag?

 

[aamirawan91]

Is the SetBitInTag function meant for a boolean tag, or is it for an integer tag?

It's a boolean tag. It is linked to a PLC memory bit. Well, not just this button. None of them are working.

 

[RClem]

You should use the 'SetBit' function, from the Siemens help file:
SetBitInTag
Description

Sets a bit in the given tag to 1 (TRUE).

After changing the given bit, the system function transfers the entire tag back to the PLC. It is not checked whether other bits in the tags have changed in the meantime. Operator and PLC have read-only access to the indicated tag until it is transferred back to the PLC.

Note

If the PLC supports BOOL tags, do not use this system function. Use the "SetBit" system function instead

 

[RVaughan]

What is the tag's acquisition cycle?

 

[aamirawan91]

Made it work by setting the "settagvalue" to 1 for "Rress" and "settagvalue" to 0 for "Release". I don't know why they didn't include the "setbitwhilekeypressed" option in wincc unified like wincc advanced, basic and comfort.

 

[drbitboy]

Made it work by setting the "settagvalue" to 1 for "Rress" and "settagvalue" to 0 for "Release". I don't know why they didn't include the "setbitwhilekeypressed" option in wincc unified like wincc advanced, basic and comfort.

you may find this unreliable. sometimes the set value to 1 will happen on press but the reset value to 0 on release will not happen. Unless the duration of the button press is important, it is better to only write a 1 to the value on the press, and then have the PLC reset the value to 0 when it detects the 1. This is called "set and forget."