Chapter 7 Function Block and Library The principles of using a symbol whose data type is POINTER, T_POINTER, C_POINTER, or HC_POINTER are as follows. 1. Only AH/AS and DVP-ES3 series CPU modules support a symbol whose data type is POINTER, T_POINTER, C_POINTER, or HC_POINTER. 2. The symbols whose data types are POINTER can only be declared in the function blocks in a project, and they must be symbols of VAR_IN_OUT class. 3. The pointers and the restrictions are described below. 7-15 Pointer Restriction General pointer POINTER Maximum 16 symbols whose data types are POINTER can be declared in a function block.
number Reference Symbol whose data type is WORD/DWORD/LWORD/INT/DINT/LINT, data register, link register, or X/Y device (e.g. X0/Y0) Pointer for a timer T POINTER _ Maximum 8 symbols whose data types are T POINTER can be declared in a _ function block. number Reference Timer or symbol whose data type is TIMER Pointer for a counter C POINTER _ Maximum 8 symbols whose data types are C POINTER can be declared in a _ function block.
number Reference Counter or symbol whose data type is COUNTER Pointer for a high-speed Maximum 8 symbols whose data types are HC POINTER can be declared in a _ counter Reference 32-bit counter or symbol whose data type is COUNTER and to which a 32-bit counter is assigned HC POINTER _