ISPSoft User Manual 6.1.4 Symbol Variable Address Allocation and Initial Value Every symbol variable is allocated to a corresponding device address based on data types and can setup an initial value . When downloading the project, users can select to write initial value in the corresponding device address of the symbol variable. Please refer to section 6.2.6 for more operation details relating to initial values. The following chart provides a description on the symbol variable address allocation principle. The allocation principle differs based on different PLC types.
6-14 Model Allocation Principle AH/AS Users can assign devices to the global symbols and the local symbols declared in the POUs of the program type. The system can also automatically assign devices to the global symbols and the local symbols declared in the POUs of the program type. The system automatically allocates the local symbols of function blocks, but does not provide allocation by users. The auto-allocated address is configures to the reserved memory section in the hosts, and do not occupy D or M device; for STEP, TIMER, or COUNTER types, the system still automatically allocate S, T and C device. DVP Users can allocate devices to all the global symbols and the local symbols.
The system can also automatically allocate devices to all the global symbols and the local symbols. The devices allocate by the system are usable devices. (Users can set a range of devices which can be allocate automatically.) AS5xx/ DVPxxMC Users can assign devices to the global symbols and the local symbols declared in the POUs of the program type. The system can also automatically assign devices to the global symbols and the local symbols declared in the POUs of the program type. The system automatically allocates the local symbols of function blocks, but does not provide allocation by users.
The auto-allocated address is configures to the reserved memory section in the hosts, and do not occupy I/Q/ M device.