Omron SYSMAC CP Series, User Manual

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4 Understanding Programming
4-14
CP2E CPU Unit Software User’s Manual(W614)
4-4 Programming Instructions
Programs consist of instructions. The conceptual structure of the inputs to and outputs from an instruc-
tion is shown in the following diagram.
z
Power Flow
The power flow is the execution condition that is used to control the execution and instructions when
programs are executing normally. In a ladder program, power flow represents the status of the exe-
cution condition.
Input Instructions
• Load instructions indicate a logical start and outputs the execution condition.
• Intermediate instructions input the power flow as an execution condition and output the power flow
to an intermediate or output instruction.
Output Instructions
Output instructions execute all functions, using the power flow as an execution condition.
4-4-1 Basic Understanding of Instructions
Structure of Instructions
Flags
Instruction
Flag
Power flow (P.F., execution condition)
Instruction condition
Power flow (P.F., execution condition)
*
1
Instruction condition*
2
Operands
(sources) Operands
(destinations)
I/O memory
*1: Input instructions only.
*2: Not output for all instructions.
Outputs the execution
condition.
=
D0
#1215
Outputs the execution
condition.
Input block
Output block
Power flow for
output instruction
LD power flow