Arithmetic instructions
382
Part III FP Instructions
F37_DEC
16-bit decrement
15 . . 12 10 . . 8 7 . . 4 3 . . 0
d
0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1
15 . . 12 10 . . 8 7 . . 4 3 . . 0
d
0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0
Result value 16 if trigger is ON
Bit
Bit
Example value 17
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.
PLC types
Availability of F37_DEC (see page 1325)
Variable Data type Function
d INT, WORD 16-bit area to be decreased by 1
For Relay T/C Register Constant
d - WY WR WL SV EV DT LD FL -
No. IEC address Set If
R900B %MX0.900.11 for an instant the calculated result is 0.
R9009 %MX0.900.9 for an instant the result exceeds the range of 16-bit
data (underflow).
Description
Subtracts "1" from the 16-bit data specified by d if the trigger EN is in the ON-state. The result is
stored in d.
Data types
Operands
Error flags
Example
In this example, the same POU header is used for all programming languages. For an example
using IL (instruction list), please refer to the online help.
POU header
All input and output variables used for programming this function have been declared in the POU
header.
Body
When the variable start is set to TRUE, the function is carried out.