WinCC Flex Programming Doubts 2

[juanmdx]

Well i structured my problem a little bit more, so that it can me more understandable and hopefuly someone can help me.

Here's what i got (on WinCC Flexible):

SF1 | SF2 | SF3 | SF4
1 4xx01 4xx02 4xx03
2 4xx11 4xx12 4xx13
.. ... ... ...
8 4xx71 4xx72 4xx73
9 4xx81 4xx82 4xx83
10 4xx91 4xx92 4xx93




So what i want is that when i change the value on SF1 the other SF's change the address they're pointing to, but that i'm still able to change their values.

Jesper (someone in the forum) told me that can be done using Tag Multiplexing, but i havent figured out yet how to do it.

Hope is understandable and someone can help me.


Juan

 

[RMA]

Do the multiplexing in the PLC, it's easier and consumes less Tags

I've not used multiplexing in WinCC Flex, because I discovered in ProTool that multiplexing eats Tags like nobody's business. Looking through the Help Files for Flex I got conflicting impressions. The description of Multiplexed addressing seems to imply that it uses only one or two Tags, the description of indirect addressing, on the other hand, clearly states that all the variables must be defined (i.e. each one requires a Tagname).

I now go the other way and do the multiplexing in the PLC.

Define a memory area, say in a DB for the output values you want to display on the OP. Define a second area to hold the input values which you enter from the OP. Then depending on the value of (in your case) SF1, map the appropriate values to the display memory.

If the operator then enters a new value, set a Flag to show the program that a new value is available in input memory and then copy this value to the appropriate memory area, depending on the contents of SF1.

 

[JesperMP]

Rant: I just hate when it all constraints are NOT defined in the original thread.

I know from another thread that Juan posted that he cannot change anything in the PLC.
That is why I suggested the tag multiplexing. I dont think that spending 30 tags is such a big issue. The constraint is that he must be able to do it all in Flexible.

 

[RMA]

I know from another thread that Juan posted that he cannot change anything in the PLC.

Ahh, I guess I missed that Thread. I saw the previous version of this Thread, but there's no mention of that constraint there, either. I guessed he would find it easier to do the mapping in the PLC, because the description of Multiplex addressing in the WinCC Help files is not even as good as (or should that simply be worse than?) the ProTool Help files.

 

[JesperMP]

He posted a lot of threads. In THIS post he said this:

So the PLC uses both tags, and the PLC program is a little long, un commented and not so structured so it's really complicated to know exactly what it does and how, so I better only send and recieve the same info and only change the panel (because that's what they told me to)

 

[RMA]

Fair enough, I understand his problem.

As you said, it would be nice if people would mention all the relevant information in each Thread. I had a few weeks where I had no, or only very restricted Internet access, so I wasn't able to catch up on everything. Under those circumstances, I tend to just skim the new posts list looking for Step7 references.

 

[juanmdx]

Sorry about using multiple threads and not posting everything on this one...

I've already learned about multiplexing tags and wrote the program, everything has been working fine, so thanks a lot for your help.


Juan