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Type
| Function |
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Description
| Reads the bit of the IN input value that is selected with the BIT input and returns the value of the selected bit. The function can operate on various input data types. |
| Notes |
- The output must have the same length or must be larger than the input.
- The value applied to the BIT input must be greater than or equal to 0 or less than the length of the IN bit string.
- If the BIT value is greater or equal than the length of the IN bit string, the function returns the value FALSE (there is no error generated in the MESSAGES window).
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Parameters
| Inputs
 IN
| Data type: | ANY_BIT |
| Description: | Input value from which the bit selected with BIT is to be read. |
BIT
| Data type: | ANY_INT |
| Description: | Number of the bit to be read. The bit number starts at position zero, i.e., the first bit is bit 0. |
Output
OUT
| Data type: | BOOL |
| Description: | Value of the selected bit. |
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Error behavior
| Error behavior
The following table shows the errors which may occur while executing the function and the value returned by the function in the corresponding error case.
| Error case | Output value |
| BIT < 0 | Last valid value is keptIf ENO is not used, FALSE is returned. |
| BIT >= bitlength(IN)(bitlength(IN) = length of the IN bit string) | Last valid value is keptIf ENO is not used, FALSE is returned. |
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Additional information
| EN/ENO behavior
The POU is only executed if TRUE is applied to the EN input. If EN = FALSE, the POU is not executed and ENO = FALSE indicates the inactivity.
If any of the errors listed under "Error behavior" occurs while executing the function, ENO is set to FALSE.
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| Example | Example in ST
MyBoolVar := GET_BIT(BYTE#2#100001,USINT#5); (* stores TRUE in MyBoolVar *)
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