Bit-shift instructions
562
Part III FP Instructions
F102_DSHR
Right shift of 32-bit data in bit units
31
00000000
0
CY
16 15
Data
[n bits]
The data in the nth bit
is transferred to R9009
(carry flag)
The [n bits] are filled with 0s
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 F102_DSHR (see page 1320)
Variable Data type Function
n INT number of bits to be shifted (range: 16#0 to 16#FF)
d ANY32 32-bit area to be shifted to the right
For Relay T/C Register Constant
n WX WY WR WL SV EV DT LD FL dec. or hex.
d - DWY DWR DWL DSV DEV DDT DLD DFL -
No. IEC address Set If
R9009 %MX0.900.9 for an instant the bit at position n - 1 has the value 1.
Description
The function shifts the value at output d to the right. The number of bits at output d to be shifted to
the right is specified by the value assigned at input n. This shift can lie between 0 and 255 (only the
lower value byte of n is effective). Bits cleared because of the shift become 0. When input n = 0, no
shift takes place. A shifting distance larger than 32 does not make sense, since when n = 32 the
value at output d is already filled with zeros. The bit at position n - 1 (the last bit shifted out to the
right) is simultaneously stored in special internal relay R9009 (carry flag) so that it can be evaluated
accordingly. When n = 0 the content of the carry flag does not change.
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.
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