FB_DALI304LightSensor

The function block is used for the configuration and operation of an instance of a DALI control device that supports Part 304 (light sensor).

Further information on the supported instance types can be found here:

Part 304 (light sensor) - Introduction

If necessary, the output value can also be queried immediately via the variable bQueryInputValue, even if the corresponding instance is not enabled.

The output variable nBrightnessLevel is written depending on the specified resolution nResolution (application and vendor-specific).

The existing parameters can be overwritten by changing the properties listed below. All parameters are written to the DALI control device by a positive edge at bInitialize and stored there.

The outputs with the output values of the DALI device only contain valid values if the function block was executed without errors (bError = FALSE). If the output bError = TRUE, the outputs with the output values must not be evaluated.

	Set the times so that as few events as possible are sent. If too many events are sent, this can have a negative effect on the behavior of the application.

	The function block cannot be used when using the KL6811.

Inputs

VAR_INPUT
  bInitialize                 : BOOL  := FALSE;
  nShortAddress               : BYTE  := 0;
  nInstanceNumber             : BYTE  := 0;
  nResolution                 : BYTE  := 10;
  bQueryInputValue            : BOOL  := FALSE;
  bGetInputNotifications      : BOOL  := TRUE;
  nOptions                    : DWORD := 0;
END_VAR

Name	Type	Description
bInitialize	BOOL	The configuration of the DALI control device is started by a positive edge at this input. During this time no DALI commands are processed.
nShortAddress	BYTE	Short address (0…63) of the DALI control device.
nInstanceNumber	BYTE	Number of the instance (0…31) of the DALI control device to be addressed.
nResolution	BYTE	Vendor-specific resolution (1...64) of the input value. The value specifies the number of bits with which the input value is scaled.
bQueryInputValue	BOOL	Immediate query of the measured value. A query is possible even if the instance is disabled via the bEnableInstance property.
bGetInputNotifications	BOOL	A TRUE at this input causes the received Input Notification Events to be output at the output.
nOptions	DWORD	Reserved for future extensions.

Outputs

VAR_OUTPUT
  bError                     : BOOL;
  ipResultMessage            : I_TcMessage;
  bInitializing              : BOOL;
  bReadingOccupancy          : BOOL;
  bReadingBrightness         : BOOL;
  bOccupied                  : BOOL;
  nBrightnessLevel           : UINT;
END_VAR

Name	Type	Description
bError	BOOL	This output is switched to TRUE if an error occurs during the execution. Further information about the error can be queried via the variable ipResultMessage. The output is set to FALSE again as soon as bBusy switches to TRUE.
ipResultMessage	I_TcMessage	Interface pointer (see error evaluation) that can be used to obtain detailed information about the processing of the function block (see runtime messages). The interface pointer is valid after bBusy has changed from TRUE to FALSE.
bInitializing	BOOL	The output is set as soon as the initialization of the DALI control device has been started, and remains active until all DALI commands have been executed.
bReadingInputValue	BOOL	The output is set as soon as the manual reading of the measured value has been started and remains active until all DALI commands have been processed.
nBrightnessLevel	UINT	Measured brightness value of the light sensor.

	This measured value must be compared with the measured reference values at the place of operation of the DALI control device.

Properties

All parameters that are written to the DALI control device via bInitialize are available as properties.

Name	Type	Access	Initial value	Description
bEnableInstance	BOOL	Get, Set	TRUE	The instance can be enabled or disabled on the DALI control device. If this property is FALSE, sending events from this instance is disabled. However, the actual value of the instance can still be queried via the input bQueryInputValue.
eEventPriority	E_DALIEventPriority	Get, Set	MiddleLow	Setting of the event priority.
nDeadtimeTimer	UINT	Get, Set	1500 ms	Dead time (0...12750 ms) to ensure that not too many events are sent in succession. An event is only sent after expiry of the dead time timer. The dead time timer is restarted each time an event is sent.
nHysteresis	BYTE	Get, Set	5 %	Value (0…25 %) for calculating a hysteresis value in order to prevent frequent and disturbing changes when measuring the illuminance.
nHysteresisMin	BYTE	Get, Set	10	Since the percentage hysteresis can lead to strong fluctuations when the illuminance is low, a minimum hysteresis can be specified via this property. The minimum hysteresis is an absolute value with a range from 0 to 255. The value depends on the resolution.
nReportTimer	BYTE	Get, Set	30 s	Time (0…255 s) after which the pending event of the light sensor is repeated if no other event has occurred in the meantime.
ipDALICommunication	I_DALICommunication	Get, Set	0	Interface pointer to the communication block (see Transfer of the reference to the communication block).

Requirements

Development environment	Required PLC library
TwinCAT from v3.1.4024.11	Tc3_DALI from v3.5.0.0