Expert - Logic startup behaviour

1.Scanning process

All communication objects are set to the initialisation value of the communication object.
The values for the retentive communication object are loaded from the memory and overwrite the initialisation value of the communication object.
With retentive KNX communication objects with a set transfer flag in the HS/FS, the value is sent to the KNX.
The Scanning/query is the KNX communication objects is started (this only affects the communication objects flagged in Expert/the communication object with "Query during starting"). A 120 second timeout is started.
If the KNX responds, queried communication objects are set to the value returned.
The timeout is reset to 120 seconds. If the timeout expires, the process is terminated with status code 2.
If the last query has been sent, the timeout is started with a runtime of five seconds. If the timeout expires, the process is terminated with status code 1.
The scan of the KNX is successfully terminated with status code 0 when all the queried communication objects have responded.

Important

Depending on the KNX data interface, a failed query can take different lengths of time. The number of successive failed queries leading to an abort varies as a result.

2.Logic initialisation

Now all logic nodes are initialised. The sequence is selected so that all logic nodes linked to the outputs are already initialised (in other words from left to right).

The following occurs during the initialisation of a logic node:

Setting of all outputs from all logic nodes to the initialisation value of the output (see documentation).
No sending of values takes place yet.
However, the setting of the outputs to a value is important for all "Send-by-Change" outputs.

Setting of all inputs to a defined value. In the process, the rules of the following table are used.
No calculation of outputs takes place yet.

Case	Fixed value	Number of COs	Number of outputs*	Value used
E1	X	0 to n	0 to n	Fixed value
E2	-	0	0	Initialisation value of the input (see documentation)
E3	-	1	0	CO
E4	-	2 to n	0	Undefined**
E5	-	0	1..n	Initialisation value of the input (see documentation)
E6	-	1	1..n	CO
E7	-	2..n	1..n	Undefined**

* = one or more other logic nodes
** = it cannot be predicted which communication object * is used for initialisation.

Importing of the retentive data of all logic nodes (e.g. elapsed operating time meter etc.). No outputs are calculated yet.
All logic nodes with "Recalculation during start = YES" are calculated. The outputs calculated during the initialisation process are dependent on the definition of the logic nodes and are contained in their documentation.
The outputs calculated during the initialisation process can set values of communication objects, execute commands and initiate recalculations in linked logic nodes. The order of the initialisation ensures that the linked logic nodes are already initialised.
Note
During the initialisation phase, all logic nodes already initialised can be initiated for recalculation by a communication object.
The System start status object is set to 1.

Note

The fixed value on the input is used if there is no connection on the input. A fixed value in combination with a connection is a special case: e.g. in connection with the use of an output of another logic node as an input value.