Using the S7 cross reference function

Hi all, im a new PLCS.net user.

im learning Siemens S7 and im jus chucking questions about all over the place to the guys teaching me. but this one im gonna answer without asking them!!! the siemens website is a nightmare to use so i found you guys and wondered if you could help me

when opening the block editor from the simatic manager you get the code from within that block in the format you choose. at the bottom there is a tab on the list that says cross refernces. i assume this is similar to the refernce data tool that can be used. i was wondering how this works. as far as i can see it it displays all the data in that particular network you have selected. i was wondering if there is any way of changing this to show other, more useful information.

if there is no way of changing it or customising this function then what could i use it for.

hopefully the first thread of many

Cheers guys

BMW APPRENTICE

The xref view from the editor shows the xref data for the network you have selected as you correctly describe. If you want to view your own filtered data, use the reference data tool.

bmw_apprentice said:

i was wondering if there is any way of changing this to show other, more useful information.

Click to expand...

bmw_apprentice,

I think you need to define what you mean by 'more useful information'.

The cross reference tab does show the data in the selected network,as you stated, but if any of those elements are used elsewhere in the program there will be a + alongside the address/name used. Click on this + sign and it will expand to show where that particular address is used, then by double clicking on the address, the program editor will jump to the relevant part of the program.

If you are learning Siemens S7's then you might find this site interesting - http://www.automation.siemens.com/fea/html_76/down_module.htm

I would also recommend buying the books by Hans Berger, either 'automating with step 7 in LAD and FBD' or 'automating with step 7 in STL and SCL'

Paul

Hi

Press Alt+Ctrl+R to open the cross reference

You can see
1) the bits,words,Double Word, No. of timers, counters etc used in your program
2)Unused symbols which you have defined but not used in your program and Vice Versa
3)Call structure of your program, i.e; which FC calling which FC,DB etc

Cheers PLucas, i hadnt really looked at it that hard to be honest. I have now had a good look at the feature and your advice helped me to understand the tool. its very useful, more so than i expected.
cheers for the link to the siemens sight, is it me or is that site hard to navigate? anyway, this is why im an apprentice and you guys are the experts

Cheers.

bmw_apprentice said:

is it me or is that site hard to navigate?

Click to expand...

It can be, once you get used to it, it's not so bad.

Even us, so called 'experts' sometimes struggle to find the exact information we are after, so I wouldn't worry too much that you find Siemens support site a struggle.

Paul