Cutler-Hammer D320 PLC, Руководство пользователя

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Chapter 6: Instructions
121
Instruction
Mnemonic Shift to Left Range
■
Bit
Word
SHL
DSHL Shift to left (high-order bit) by N
bits
Lowest bit becomes 0
Double words
Ladder
D = Register address
N = Number of bits to rotate
Description
1. Order:
Shift N bits to the left (from low-order bit to high-order bit) including the carry bit.
The MSB (most significant bit) moves to the carry bit (F1.8).
The LSB (least significant bit) becomes 0.
2. Shift the register specified as D to the left by N bits. Each bit will move one position higher in
the register.
3. The D register is either a word or a double word. For SHL (word), N = 0 to 15. For DSHL
(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.
SHL
D =
N =
R
MSB
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
LSB
carry
(F1.8)
C p o n m l k j i h g f e d c b a 0