Mitsubishi MELSEC Q Series, Programming Manual

Page: 379 / 816

7.2 Rotation Instructions
7.2.4 Left rotation of 32-bit data
7-39
7
APPLI
C
A
T
IO
N
INSTRUCTIONS
DROL, DRCL
DROL, DRCL
(3) Specify any of 0 to 31 for n.
If the value specified for n is 32 or higher, the remainder of n divided by 32 is used for
rotation. For example, when n 34, the remainder of 34/32 1 is 2, thus the data are
rotated 2 bits to the left.
DRCL(P)
(1) Rotates 32-bit data of the device specified for , including the carry flag, n bits to the left.
The carry flag turns ON or OFF depending on its status prior to the execution of the DRCL
instruction.
(2) When a bit device is specified for , a rotation is performed within the device range
of points by digit specification. The number of bits that rotate is the remainder of n divided by
‘number of points by digit specification’.
For example, when n 31 and ‘number of points by digit specification’ 24 bits, the
remainder of 31/24 1 is 7, thus the data are rotated 7 bits.
(3) Specify any of 0 to 31 for n.
If the value specified for n is 32 or higher, the remainder of n divided by 32 is used for
rotation. For example, when n 34, the remainder of 34/32 1 is 2, the data are rotated 2
bits to the left.
O peration Error
No operation error occurs in the execution of the DROL(P) and DRCL(P) instructions.
Program Example
(1) In the following program, the data in Var_D0 are rotated, not including the carry flag, 4 bits to
the left, when X0C turns ON.
[Structured ladder]
[ST]
DROLP(X0C,4,Var_D0);
[Operation]
d
b2 b16 b31 b17 b30 b29 b28 b27 b18 b15 b1 4 b5 b 4 b3
C arr y flag
(SM700)
b1 b0
n- b it rotation
d
d
1 Var_D 0 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0
0 Var_D 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1
b31 b16 b0 b15 b28b27 b2 4 b23 b20b19 b12 b11 b8 b7 b 4 b3
C ontents of b31 to b28
b efore execution
C ontents of b27 to b0
b efore execution
0
1
C arr y flag
(SM700)
C arr y flag
(SM700)
C ontent of b28
b efore execution
b31 b16 b0 b15 b28b27 b2 4 b23 b20b19 b12 b11 b8 b7 b 4 b3