Hi Julian,

so I spun up my TIA and did some String stuff ...

Defined 2 Sting variables:

Name:           Data type:              Offset:         Start value:
Hurz1           String                  314.0           'Der Wold, das Lamm"
Hurz2           String                  570.0           'Auf der grünen Wiese"

After compiling the memory block (DB1), the offsets were automatically set.

Then I added a CONCAT function to my PLC program and referenced those two 
fields as input. Here's what TIA made out of it:
Hurz1:  P#DB1.DBX314.0
Hurz2:  P#DB1.DBX570.0

Notice the "P#" instead of the "%"? And it seems that the address looks like a 
BIT address, as it has the bit offset part set. But just comparing this to all 
the others, it seems like all types can have a bit-offset part set, this is 
just always ".0" for any non-bit type.

Chris


Am 02.09.18, 13:03 schrieb "Julian Feinauer" <[email protected]>:

    Hey everybody,
    
    I have another question about the semantics we should provide for reading / 
writing Strings in the S7 Driver.
    I have not found an example on how this is handled currently but to me it 
looks a bit like a mix of reading the data as “array”, i.e., using the size 
parameter on the request (= fixed size string) but handling it as null 
terminated String.
    
    As I have currently no TIA available, can anyone give me the syntax how 
Strings are addressed in TIA.
    I think they were fixed size always and I would prefer to do it that way.
    
    Could anyone who implemented this (or has expertise in this) help me out a 
bit?
    
    Thanks
    Julian
    

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