BIT_TST block
Short summary
Name |
BIT_TST |
→POU type |
|
Category |
|
Conform to →IEC-standard |
not defined in IEC-standard |
Graphical interface |
|
Available since |
|
Functionality
The block returns the result for the determination of a bit value (as value TRUE or FALSE – or alternatively equivalents for them).
At input IN, enter a value. At input N, enter the bit number (0-based) that should be tested.
Inputs, return value
|
Identifier |
Description |
|
Inputs: |
IN |
BOOL, BYTE, WORD, DWORD or LWORD(corresponds to →generic data type ANY_BIT) |
input value |
N |
USINT |
the bit number (0-based) to test |
|
Return value: |
– |
BOOL |
|
Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.
See:
"Blocks for safe logic" whether this block is supported for developing safety-relevant applications.
"Highlighting safe logic in the FBD-editor" for the effects when using the block as a block for safe logic .
Example for usage within ST-editor
PROGRAM Test
VAR
result1, result2 : BOOL;
END_VAR
result1 := BIT_TST(IN := DWORD#
16
#
80000003
, N :=
2
); (* The variable
'result1'
evaluates to
'BOOL#0'
. *)
result2 := BIT_TST(IN := LWORD#
16
#
8000000000000003
, N :=
63
); (* The variable
'result2'
evaluates to
'BOOL#1'
. *)
END_PROGRAM
When creating your application within the ST-editor, enter a call of a block by typing the text as requested by the syntax or use Content Assist.