Hello!

Siemens says: "The programming languages of SIMATIC STEP 7 (TIA Portal) meet the requirements of IEC 61131-3" (https://support.industry.siemens.com/cs/ww/en/view/50204938).  

Unfortunately not in 100%. In this file (http://d1.amobbs.com/bbs_upload782111/files_31/ourdev_569653.pdf) page 33 you can find that IEC 61131-3 allows creating non-structured user data types e.g.:

TYPE ANALOG_DATA : INT (-4095..4095) ; END_TYPE

I have prepared External Source File containing such line but TIA cannot generate udt. If I remove range "(-4095..4095)". It generates ANALOG_DATA type but its empty. In the other file I found that TIA allows only STRUCT in UDTs.

Conclusion is: SIMATIC STEP 7 (TIA Portal) meet the requirements of IEC 61131-3 but not in 100%.

Am I right? If not please correct me?

Best regards!