Examine If Open (XIO)
    The XIO instruction examines the data bit to set or clear the rung condition.
Available Languages
Ladder Diagram
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Operands
Ladder Diagram
| Operand | Data Type | Format | Description | 
|---|---|---|---|
| Data bit | BOOL | tag | Bit to be tested. There are various operand addressing modes possible for the data bit, see Bit Addressingfor examples.  | 
Affects Math Status Flags
No
Major/Minor Faults
None specific to this instruction. See Index through arrays for array-indexing faults.
Execution
Ladder Diagram
| Condition/State | Action Taken | 
|---|---|
| Prescan | N/A | 
| Rung-condition-in is false | Set Rung-condition-out to Rung-condition-in | 
| Rung-condition-in is true | If Data Bit is true, rung-condition-out is cleared to false. If Data Bit is false, rung-condition-out is set to true. | 
| Postscan | N/A | 
Examples
Example 1
Ladder Diagram

If Limit_Switch_01 is false, the next instruction is enabled.
Example 2
Ladder Diagram

If S:V is false, this enables the next instruction.
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