Cutler-Hammer D320 PLC, Руководство пользователя

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Chapter 6: Instructions
117
Instruction
Mnemonic Rotate to the Right Without Carry Range
Bit
■ Word
RRC
DRRC Rotate the specified address to the
right (high to low)
■
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).
Fill the carry bit (F1.8) with the LSB (least significant bit).
Shift the LSB to the MSB (most significant bit).
2. Shift the register specified as D to the right by N bits. Each bit will move one bit position
lower in the register.
3. The D register is either a word or a double word. For RLC (word), N = 0 to 15. For DRLC
(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
Initial condition: M0000 = $0F0F
M0001 = $0F0F
M0002 = $0F0F
Operation results: M0 = $8787
M1 = $C3C3
M2 = $C3C3
RRC
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
a
RRC
D = M0000
N = 1
DRRC
D = M0001
N = 2
R0.0
R
0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1
1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1
1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1