I want to expose a value to the knx bus in an automation.
How can i do this?
Best regards,
Stefan
Use the knx.send service to send data to knx bus.
If you want to expose a state or attribute of an entity you can configure expose.
If you want to configure an expose in an automation (eg when writing a blueprint) you’ll have to wait for
(or maybe give it a review
)
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Thanks for the quick reply. I’m not sure if that’s what it need.
I already added an exposure in the configuration.yaml but i want to force this exposure to send the value to the bus at a specific time/trigger.
The value is the current time and date. Can i do it with knx.send?
Current date and time works with knx.expose as mentioned above.
This how I have it in my configuration:
knx:
expose:
- type: “datetime”
address: “0/0/1”
- type: “time”
address: “0/0/2”
Right. It will send once an hour.
If you need to send custom time (not localtime) you could try knx.send with raw byte values.
Thats what i’m doing. But i do have an KNX-Device that can request a time update.
Therefore i would like to add this as an automation.
Devices asks on 5/0/3 for time update --> triggers automation --> sends exposed current time.
If your device asks for an update with a GroupValueRead the expose: time / date / datetime will answer with current localtime.
The device triggers this on a different GA. I don’t know why 
Hello,
A small problem with datetime sent by HA. Here is my configuration
knx.yaml file
exposes:
- type: ‘datetime’
address: ‘8/6/2’
In GA 8/6/2, the object 505 (datetime) of the ABA / S 1.2.1 logic controller and a datetime object of the ABA are linked, which allows a connection to the functions implemented in the ABA.
With the group monitor, if I read the GA 8/6/2, I have the datetime return, but while letting the telegrams scroll in the monitor, I do not see a telegram passing with a DPT 19.001, although it should appear every minute?
No, it is sent once an hour. I think on init and then periodically, so not every full hour, but an hour after startup.
Thank you. I am going to test with Time which must send well every minute?
No it’s the same. Why should it send every minute - every hour is more than enough.
In my KNX installation I have an advanced logic controller (ABA / S1.2.1) with calendars and some 30-minute programs for example.
Time in KNX is used to initialize and sync internal clocks, not to provide a minute-signal. Especially when it is an “advanced” logic controller it is surely able to keep its own time for hours / days without drifting significant.
When such devices are restarted they usually send a GroupValueRead - which will be answered by a GroupValueResponse. This way you can also test your time exposure from ETS group monitor.
Thanks for the explanation. I left the group monitor running and HA does send “time” and “datetime” once per hour.
I made an error by imagining an operation other than that of synchronization but my problem remains intact: how to display in HA the value of the datetime when a KNX output goes to 0?
I’m not sure I understand your question right.
If you want to know when (current local time) a telegram (eg. with payload 0) to a specific group address was sent: I’d listen to knx_event and parse the events “time_fired” attribute.
(In the next version sensors and binary_sensors will also have a timestamp as extra_state_attribute).
If you want to parse the payload of a datetime telegram (DPT 10, 11, 19) - not the current local time - then this is not supported by the HA knx integration.
