Arithmetic instructions
342
Part III FP Instructions
F20_ADD
16-bit addition
15 . . 12 10 . . 8 7 . . 4 3 . . 0
d
0 0 0 0 0 0 0 0 0 0 0 1 1 0 1 1
15 . . 12 10 . . 8 7 . . 4 3 . . 0
s
0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0
15 . . 12 10 . . 8 7 . . 4 3 . . 0
d
0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 1
Example value 27
Bit
Example value 16
Bit
Result value 43 if trigger is ON
Bit
This instruction also exists as a P instruction (for FP2/2SH, FP3/5, FP10/10SH PLC types), which
is only executed at the rising edge of the EN trigger. Select [Insert P instruction] from the
"Instructions" pane if you require a P instruction. To facilitate reuse, the instruction then appears
under "Recently used" in the pop-up menu. Press <Ctrl>+<Shift>+<v> within the programming
area to open the list of recently used elements.
Instead of using this FP instruction, we recommend using the related IEC instruction ADD (see
page 61). Please refer also to Advantages of the IEC instructions in the online help.
When this instruction is used, the area for the augend d is overwritten by the
added result. If you want to avoid the overwrite, we recommend using the
instruction F22_ADD2 (see page 345).
PLC types see see page 1322
Variable Data type Function
s addend
d
ANY16
augend and result
The variables s and d have to be of the same data type.
Description
The 16-bit equivalent constant or 16-bit area specified by s and the 16-bit area specified by d are
added together if the trigger EN is in the ON-state. The result is stored in d. All 16-bit values are
treated as integer values.
Data types