S7 different code/data assignment offline/online.

Greetings PLC afficionados.

Someone tell me why there is such a difference between what memory requirement is reported between:
STEP7 offline: "Size in work memory" code 27kB data 3kB
STEP7 online: "module information - Work memory" code 56kB data 12 kB.


I have used "compress" - made no difference.
PLC is S7 412-2DP.

Of course I would like to have as much memory available as possible, so the actual online info is a bit disapointing

Replying to my own post (sad, isn't it):

The actual (online) memory assignment also contains the hardware config, communication jobs, retentive merker memory etc.

There is a button when viewing "module information": "Details memory area" that will provide just that.

Then I'm only a little mad at STEP7 for not providing an offline information about the total memory requirement for the application (maybe there is somewhere, but where ?).

There is-
Right click on blocks (from the Simatic Manager)
Object Properties-> Blocks Tab
Bingo
There's your work memory and load memory size

Hi

there is a Program called 'Calculator 4.0'
You can find it here:
http://www4.ad.siemens.de/WW/llisapi.dll?func=cslib.csinfo&lang=en&objid=16770205


regards

Rolf

JRW,
what you write is what I thought too, but doing so will NOT tell you the actual TOTAL memory requirement ! Only for the blocks. Try yourself to compare what OFFLINE Blocks .. Properties says and what ONLINE module information says.

RolfB,
thanks, but that program will only make a rough estimate of how big a CPU you should choose.

Possibly it is mistake only in step7 developer ?

I have just had it confirmed from Siemens hotline, that STEP7 OFFLINE does not inform the total memory requirement - only the memory requirement for the code and data blocks that you have defined yourself.