Avatar

Please consider registering
guest

sp_LogInOut Log In sp_Registration Register

Register | Lost password?
Advanced Search

— Forum Scope —




— Match —





— Forum Options —





Minimum search word length is 3 characters - maximum search word length is 84 characters

sp_Feed Topic RSS sp_TopicIcon
How to get notification when an OPC UA array variable is modified?
August 11, 2014
10:38, EEST
Avatar
Allan
Member
Members
Forum Posts: 11
Member Since:
July 22, 2014
sp_UserOfflineSmall Offline

If I create an array using a method like SampleConsoleServer.createAnalogItemArray(), how can I arrange to be notified when the array is modified?

I tried using a method like SampleConsoleClient.subscribe(NodeId nodeId), but that does not seem to work for array variables created by this method.

I would have expected that the client’s DataChangeListener would be notified when the server calls node.setValue() on the return value from createAnalogItemArray().

August 11, 2014
12:44, EEST
Avatar
Allan
Member
Members
Forum Posts: 11
Member Since:
July 22, 2014
sp_UserOfflineSmall Offline

After some experimenting, I found out that the callbacks in the client are only called if the array reference itself is new.
If the same array is used and only the contents are updated before calling setValue(), nothing happens.

August 11, 2014
13:03, EEST
Avatar
Jouni Aro
Moderator
Moderators
Forum Posts: 1009
Member Since:
December 21, 2011
sp_UserOfflineSmall Offline

Yes, it seems that the array elements are not compared, when the method checks if the value is really changing. However, it should compare the timestamps as well – depending a bit on whether you use setValue(DataValue) or setValue(Object). The latter will create a new timestamp using the current time. If you use the former, make sure that your timestamp changes.

Forum Timezone: Europe/Helsinki

Most Users Ever Online: 518

Currently Online:
25 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Top Posters:

hbrackel: 135

pramanj: 86

Francesco Zambon: 81

ibrahim: 75

rocket science: 75

Sabari: 62

kapsl: 57

gjevremovic: 49

Xavier: 43

TimK: 41

Member Stats:

Guest Posters: 0

Members: 707

Moderators: 16

Admins: 1

Forum Stats:

Groups: 3

Forums: 15

Topics: 1465

Posts: 6252

Newest Members:

christi10l, ahamad1, Flores Frederick, ellenmoss, harriettscherer, shanonhumphreys, KupimotoblokfuB, tamhollander5, paulinafcf, bridgette18l

Moderators: Jouni Aro: 1009, Otso Palonen: 32, Tuomas Hiltunen: 5, Pyry: 1, Petri: 0, Bjarne Boström: 982, Heikki Tahvanainen: 402, Jukka Asikainen: 1, moldzh08: 0, Jimmy Ni: 26, Teppo Uimonen: 21, Markus Johansson: 42, Niklas Nurminen: 0, Matti Siponen: 319, Lusetti: 0, Ari-Pekka Soikkeli: 5

Administrators: admin: 1