Siemens PLC Difference between FB and FC's characteristic FC FB Can be called as a subroutine Yes Yes Can assign parameters to Input/Output/InOut Yes Yes Temporary variables can be used Yes Yes Can use static variables (can be kept) No Yes Requires instance data block (per call) No Yes Parameters passed as addresses to internal use Yes No Parameters are passed to the internal use via the instance data block No Yes Can call FB or FC Yes Yes Can be called by … Continue reading Difference between FB and FC’s Siemens PLC