WinCC Newbie - Help Anyone?

I am currently converting a relay-based control panel to an S7-200 PLC. Everything is done, apart from the "Start" button. I need to write a value to the PLC from the button, i.e. When the "Start" button is clicked, I need to write the value of 1 to M0.2 (Start_Dedusting). When it is clicked again, I need to write the value of zero to it.

I have written a small C-Script to do this, but I am fairly sure this is incorrect.

GetTagBit("Start_Dedusting,0)
if ("Start_Dedusting,1)
SetTagBit("Start_Dedusting,1)
else
SetTagBit("Start_Dedusting,0)

The main body of it is above. The header was automatically created. I haven't tested it yet, but I'm fairly sure this is incorrect.

Can anyone tell me whether I'm on the right track or not?

Cheers.

Look at using a switch not a button. You can set it up to do just what you want and you can make it look like a standard button.

On second thought you could also use the invert bit event.


Take a look here page 165
http://support.automation.siemens.com/WW/view/en/18796010

The switch is used in runtime to input and visualize two states, for
example, ON and OFF, or pressed and not pressed.
It can be labeled with text or a graphic that indicates the runtime status of​

the switch.

Click to expand...

I should have mentioned I'm using WinCC V6.0 SP4, and not Flex. Just spent an hour looking for those dang switches... No invertbit command either. Would've been perfect that...

Hmm... No more answers. Surely someone must've done this before? Anyway, after browsing through the manuals for an hour or so, I believe my script above should work. If anyone has any other suggestions though, I'd love to hear it. Cheers.