ISPSoft User Manual AH5X1, AH560 Redundant System, AHxxEMC, and AS Series The memory blocks that an AH5X1, AH560 Redundant System, AHxxEMC, or ASseries CPU module reserves for function block instances are stored in the internal memory. That means it will not take up the device resources while allocating. The difference is for AH5X1, AHxxEMC, AS series, the number of memory blocks assigned to the function block instances can be as large as the size of the PLC internal memory, but for AH5X0, the limitation is 4096 words. And one function block instance occupies one P device.
The following diagram adopts section 7.2.6 example, including an estimated amount of local and global symbol data types declared in the function block definition. Following figure illustrates how the internal memory occupies in the instances. 7-28 Function block Number of local/global symbols definition Function block A One symbol whose data type is DWORD. One symbol whose data type is LREAL. One inferior function block instance. Function block B One symbol whose data type is WORD. Two symbols whose data type is REAL. Two inferior function block instances. Function block C Two symbols whose data type is BOOL. One symbol whose array type is BOOL and whose array size is 22 elements.
Function block D One symbol whose data type is WORD.