I have a custom data reference which works correctly in PI System explorer and PI processbook (display). Both the GetValue and GetValues functions have been implemented.
When I have one or many tags on the PI processbook (display) all the CDR attributes return the correct value. However, if I place a trend object into the display then all the CDR attributes return "Specified cast is not valid.". I have not even assigned any tags to the trend object yet.
What is the CDR code doing wrong that a trend object on the display causes it to fail?