wincc flex multiplexing with internal tag

I am a little confused by a program that I am looking at.
So If I got this correct multiplexing is using indirect addressing (Which points to an address that points to another address). in wincc flexible so that you can use just one screen and look at say 3 different motors, but all the same data descriptions? I got the example program from siemens and theirs has the index with an address what happens when it doesn't have the address?

http://support.automation.siemens.c...lib.csinfo&lang=en&objid=21807421&caller=view

in the wincc flex program in is something like DB[Tag_Description]DBW278 when i Look at tag_description there is no address?

Tommycai said:

I am a little confused by a program that

in the wincc flex program in is something like DB[Tag_Description]DBW278 when i Look at tag_description there is no address?

Click to expand...

If Tag_Description value = 60 then DB60.DBW278 is accessed.

Tag_Description can be an internal tag. Internal tags are tags that is only used internally in WinCC Flexible. and never transfered to the PLC.

If Tag_Description is an internal tag and it and you cant find find any assignments of the tag using the cross reference tool in Flexible chances are that the internal tag is configured with a initialization value. Look under the properties for the Tag_Description. If you want add an io field to a screen and assign the Tag_Description tag to the iofield then you can monitor the tag value for debugging purposes.

sorry to bring this back up after so long but I did do the cross reference in WinCC Flexible and it has a bunch of other tags? It looks like they are tabbed over. It looks like
S0_00_DBNumberData and under infotext it states <no address> in the next tags it is named SS_00_ScreenIdentification_0 under infotext DB[S0_00_DBNumberData]DBW120.

So this is accessed somewhere in the HMI to change the value of SS_00_DBNumberdata for the DB and then it accesses Word 120?

So If I got this correct, multiplexing is using indirect addressing (Which points to an address that points to another address).

Click to expand...

An indirect address is an address with a Pointer. The Pointer refers to a second memory address, where the 2nd address may contain a value, or even a 3rd address.

But I have not heard indirect addressing called multiplexing. What I have heard called multiplexing is using Inputs or Outputs for more than one function, at different times or under different situations. For example, using 3 bit addresses to input 7 different functions (binary 111).

Tommycai said:

sorry to bring this back up after so long but I did do the cross reference in WinCC Flexible and it has a bunch of other tags? It looks like they are tabbed over. It looks like
S0_00_DBNumberData and under infotext it states <no address> in the next tags it is named SS_00_ScreenIdentification_0 under infotext DB[S0_00_DBNumberData]DBW120.

So this is accessed somewhere in the HMI to change the value of SS_00_DBNumberdata for the DB and then it accesses Word 120?

Click to expand...

A qualified(?) guess:
You use a motor icon or a button to open your mulitplexed screen.
In the icons properties (events/on click) you add a command line that put the value of the actual motors instance DB number into the multiplex tag. And then a command line to open the screen with the multiplexed motor data on it.

This was messy written, but I hope you can interpret it.

Kalle