ADD ladder logic instruction

The Add instruction is a ladder logic rung output instruction that adds two values. The instruction is enabled when the preceding logic is true and disabled otherwise.  Source A is added to Source B and placed in the Destination tag. The values can be constants, tags or any combination.

List of possible arguments

SOURCE A and SOURCE B can be any combination of the following data types.

  • CONSTANT             Can’t be the DESTINATION obviously
  • SINT              
  • INT
  • DINT
  • REAL

Note: Negative numbers are valid. Arithmetic status flags are affected (S:V, S:Z, S:N, S:C). Overflow, Zero, Negative, and Carry.

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