Cutler-Hammer D320 PLC, User Manual

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120
D320 PLC User's Manual
Instruction
Mnemonic Rotate to the Right Range
Bit
■ Word
ROR
DROR Rotate the specified address to
the right with the carry flag
■
Double words
Ladder
D = Register address
N = Number of bits to rotate
Description
1. Order:
Shift N bits to the right (from high-order bit to low-order bit) including the carry bit.
Input the carry bit (F1.8) to the MSB (most significant bit).
The LSB (least significant bit) moves to the carry bit (F1.8).
2. This instruction is different from the RRC instruction because it sends the LSB to the carry
bit, and the carry bit shifts to the MSB. The input to the MSB can be changed by setting or
clearing the carry bit.
3. The D register is either a word or a double word. For ROR (word), N = 0 to 15. For DROR
(double word), N = 0 to 31.
4. This operation will occur on every scan for which the input condition is true (On). To perform
the operation only on a change of input condition, use the rising/falling edge contact.
Example
Program Expression Operation Results
ROR
D =
N =
R
MSB LSB
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
C carry
(F1.8)
p o n m l k j i h g f e d c b a
C
R0.0
R0.1
R
ROR
D = M0
N = 2
F1.8
(OUT)
$4000 $1400
$0000 $5000
MO
C 0 0 0 0 1 0 1…
C 1 0 1 0 1 …
C 1 0 1 0 0 … 0 0 C
0 0 0 0 …
MSB LSB
R0.0
R0.1