1-45
Section 1 Specications
Symbol Size
X BOOL (1 bit)
W Word (16 bits)
D Double word (32 bits)
Symbol Size
%I Identies an external input area.
%Q Identies an external output area.
%M Identies an internal memory area.
<Format for address assignment>
I/O address Refer to “1-4” for address assignments.
Prefix
Memory size
G
Key points:
• To assign 32-bit DINT or DWORD type variables, 32-bit array type variables, and structure type variables to real
addresses
(AT specication), assign them to even addresses.
(Example)
• To divide a 32-bit data type into 16-bit data type for processing, the upper and lower words are assigned as shown
below.
31 16 15 0
32-bit data Upper Lower
15 0
16-bit data Lower
Upper