- It seems that when I call EasyDAClient::SubscribeItem, the callback gets fired with the old (current) value from the OPC server even though the value hasn't changed yet. Is this by design? If yes, is there an option to fire the callback only when the value has truly changed?
- If the above is true, consider the following chain of events: 1) I subscribed to an item, 2) the library has acquired the old value and is ready to send it to the user, 3) the item has just changed, 4) the library acquired the new value and is ready to send it to the user. Is it guaranteed that the old value will arrive before the new value?
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Callback gets fired even when value hasn't changed - by: aris
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