Siemens SIMATIC PCS 7 Operating Manual page 17

You can find additional information on this topic in the FAQ "Why does the error message
"Maximum length of code area reached (max. 64 KB)" or "Insufficient main memory"
appear when the CFC charts are compiled?"
(https://support.industry.siemens.com/cs/ww/en/view/771569).
2. In the "Areas Reserved for Other Applications" field, set the value for "FC numbers from:"
to 0. The default setting is 60.
Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB
Advanced PCS 7 ES settings
5.2 CFC settings for compiling and downloading
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