GET_BIT: Reading bit

Function description

This function reads the bit selected with BitNumber for input InputRegister and writes the current state to output CurrentState.

The output is the current state of the selected input data bit.

The BitNumber parameter shows which input data bit to select.

and can be configured as additional parameters.

Representation in FBD

Representation:

Representation in LD

Representation:

Representation in IL

Representation:

LD InputRegister
GET_BIT BitNumber
ST CurrentState

Representation in ST

Representation:

CurrentState := GET_BIT(InputRegister, BitNumber);

Parameter description

Description of input parameters:

Parameter	Data type	Description
InputRegister	WORD	Input word
BitNumber	UINT	Bit number to be read.

Description of output parameters:

Parameter	Data type	Description
CurrentState	BOOL	Current state of selected bit.

Runtime error

For a list of all block error codes and values, see Extension/Compatibility.

EN stands for ENable; it is an optional block input. When the EN input is enabled, an ENO output is set automatically.

If EN = 0, the block is not enabled; its internal program is not executed, and ENO is set to 0.

If EN = 1, the block's internal program is run and ENO is set to 1. If an error occurs, ENO is set to 0.

If the EN input is not connected, it is set automatically to 1.

ENO

ENO stands for Error NOtification; this is the output associated with the optional input EN.

If ENO is set to 0 (because EN = 0 or in case of an execution error):

the status of the function block outputs remains the same as it was during the previous scanning cycle that executed correctly;
the output(s) of the function, as well as the procedures, are set to "0".

WORD

The type WORD is encoded in a 16 bit format and is used to perform processing on series of bits.

This table shows the upper/lower limits of each of the bases that can be used:

Examples of representation

Data	Representation in one of the bases
0000000011010011	16#D3
1010101010101010	8#125252
0000000011010011	2#11010011