Function Block Specifications - Omron CX-PROGRAMMER V8.1 Operation Manual

This section provides specifications for reference when using function blocks, including specifications on function blocks,
instances, and compatible PLCs, as well as usage precautions and guidelines.
2-1 Function Block Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1-1 Function Block Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1-2 Function Block Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2 Data Types Supported in Function Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2-1 Basic Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2-2 Derivative Data Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3 Instance Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3-1 Composition of an Instance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3-2 Parameter Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3-3 Operating Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4 Programming Restrictions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4-1 Ladder Programming Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4-2 ST Programming Restrictions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4-3 Programming Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-5 Function Block Applications Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-5-1 Deciding on Variable Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-5-2 Determining Variable Types
(Inputs, Outputs, In Out, Externals, and Internals). . . . . . . . . . . . . .
2-5-3 AT Settings for Internal Variables. . . . . . . . . . . . . . . . . . . . . . . . . . .
2-5-4 Array Settings for Input-Output Variables and Internal Variables . .
2-5-5 Specifying Addresses Allocated to Special I/O Units . . . . . . . . . . .
2-5-6 Using Index Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-6 Precautions for Instructions with Operands Specifying the First
or Last of Multiple Words . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-7 Instruction Support and Operand Restrictions . . . . . . . . . . . . . . . . . . . . . . . .
2-8 CPU Unit Function Block Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-8-1 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-8-2 Operation of Timer Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-9 Number of Function Block Program Steps and Instance Execution Time . . .
2-9-1 Number of Function Block Program Steps. . . . . . . . . . . . . . . . . . . .
2-9-2 Function Block Instance Execution Time. . . . . . . . . . . . . . . . . . . . .

Function Block Specifications

SECTION 2
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