Cutler-Hammer D320 PLC, Руководство пользователя

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D320 PLC User's Manual
How to Read the Description of Instructions
Each instruction is explained in three parts: the instruction itself, its ladder diagram, and a description.
This section explains how to read the instructions.
Sample Instruction
Mnemonic Substitution Formula
(Assignment expression) Range
Bit
■ Word
LET
DLET Direct substitution of number
(direct output of number)
■
Double words
Explanation of Codes
= unavailable option
■
= available option
$xx indicates a hexadecimal number.
Explanation of Table
•
Mnemonic—A word instruction, D designates double word instruction.
•
Assignment expression—Description of the instruction.
•
Range—Size of data that can be used by this instruction.
Sample Ladder
D: Destination
S: Source
Example: S = M0, and M0 is 123
D = R3, and R3 is 456
Before execution: M0 = 123, R3 = 456
After execution:
M0 = 123, R3 = 123
Explanation of Ladder
The ladder diagram shows the structure of the instruction as it is displayed. Additional text typically
gives an example and explains the processing structure.
LET
D =
S =
R