FB_ALY_DetectValueChange_1Ch

The Detect Value Change 1Ch detects and counts changes in numeric input values.

Syntax

Definition:

FUNCTION_BLOCK FB_ALY_DetectValueChange_1Ch
VAR_INPUT
    bPersistent: BOOL;
END_VAR
VAR_OUTPUT
    ipResultMessage: Tc3_EventLogger.I_TcMessage;
    bError: BOOL;
    bNewResult: BOOL;
    bConfigured: BOOL;
    bValueChanged: BOOL;
    nCount: ULINT;
    fbTimeLastEvent: FB_ALY_DateTime;
END_VAR

Inputs

Name	Type	Description
bPersistent	BOOL	If the value is `TRUE`, the internal data is stored persistently.

Outputs

Name	Type	Description
ipResultMessage	I_TcMessage	Contains more detailed information on the current return value. This special interface pointer is internally secured so that it is always valid/assigned.
bError	BOOL	This output is `TRUE` if an error occurs.
bNewResult	BOOL	When a new result has been calculated, the output is `TRUE.`
bConfigured	BOOL	Displays `TRUE` when the function block is successfully configured.
bValueChanged	BOOL	`TRUE`, if a change of value was detected, otherwise `FALSE`.
nCount	ULINT	Incremented when the output value is `bValueChanged=TRUE`.
fbTimeLastEvent	FB_ALY_DateTime	Timestamp of the last detected value change.

Methods

Name	Definition location	Description
Call()	Local	Method for calculating the outputs for a specific configuration.
Configure()	Local	General configuration of the algorithm with its parameterized conditions.
Reset()	Local	Resets all internal states or the calculations performed so far.
SetChannelValue()	Local	Method for passing values to the algorithm.

Sample

VAR
    fbDetectValueChange : FB_ALY_DetectValueChange_1Ch;
    fbSystemTime : FB_ALY_GetSystemTime;
    fTolerance : LREAL := 0.1;
    bConfigure : BOOL := TRUE;
    fIn : LREAL;
END_VAR

// Get current system time
fbSystemTime.Call();

// Configure algorithm
IF bConfigure THEN
    bConfigure := FALSE;

    fbDetectValueChange.Configure(fTolerance);
END_IF

// Call algorithm
fbDetectValueChange.SetChannelValue(fIn);
fbDetectValueChange.Call(fbSystemTime.tSystemTime);

Requirements

Development environment	Target platform	Plc libraries to include
TwinCAT v3.1.4024.0	PC or CX (x64, x86)	Tc3_Analytics

Further Information