S5 AWL Command: ON (OR NOT)
S5 AWL instruction ON (OR NOT): Negated OR operation. Syntax, S7 equivalent, and code examples.
S5 AWL Command: ON (OR NOT)
The ON instruction performs a logical OR NOT operation. It reads a boolean operand, negates it, and ORs the result with the current VKE.
Syntax
ON <operand>
S7 Equivalent
| S5 AWL | S7 STL | S7 SCL |
|---|---|---|
ON E 0.2 | ON I 0.2 (EN) / ON E 0.2 (DE) | ... OR NOT Input_0_2 |
Code Example
U E 0.0 // Normal start condition
ON E 0.2 // OR if emergency stop is NOT pressed
= A 4.0
A 4.0 is TRUE when E 0.0 is TRUE or E 0.2 is FALSE.
Related Commands
- O (OR) — OR without negation
- UN (AND NOT) — AND with negation
Part of the S5 AWL Command Reference. Maintained by PLCcheck.ai.
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