S7 Pointer Questions

arocon

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Oct 2006
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Could anyone please explain me what are the different cases Pointer to be used in Simatic S7 programming ?

Thanks
 
Here's a few that I found :)

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Can somebody explain to me when to use pointers and indirect addressing and when to not?
When I have to program I always think of direct addressing can't seem to break that habit.
 
Simple example - you wish to display the status of a user selectable variable on a HMI. You select the data area and the address on the HMI, then use indirect addressing in the PLC to return the value of said variable.
 
Think about what L D said
So now theres only one tag (maybe 2 for the selected value) used in the HMI (even though you can select 32 values)

See efficient right??

Another simple example of indirect addressing
You have 50 drives and want to know the condition of the 3rd bit (alarm) in all 50 words
Would you write 50 rungs or networks?
Alot of work..right?
Or would you indirectly "look at the 3rd bit and loop through the 50 words?
 
JRW said:
Think about what L D said
So now theres only one tag (maybe 2 for the selected value) used in the HMI (even though you can select 32 values)

See efficient right??

Another simple example of indirect addressing
You have 50 drives and want to know the condition of the 3rd bit (alarm) in all 50 words
Would you write 50 rungs or networks?
Alot of work..right?
Or would you indirectly "look at the 3rd bit and loop through the 50 words?
Click to expand...

I think by joe I get it. Although in the past I have done the later and it took for ever what was I thinking:doh:
 

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