Applies To:
  • CitectSCADA 5.31, 5.40, 5.40 Service Pack A

The "offset" argument of TrnGetBufValue() now supports a value of -1. This will cause the most recent valid sample value for a pen to be returned, provided it is less than 1.5 sample periods old. If it is older than this, TrnGetBufValue() will assume that a sample has been missed and return a value of 0.0 and a hardware alarm will be generated.

Using this feature will prevent spurious hardware alarms from being generated.

This feature has been in Citect for Windows since V5.31, but was not documented.


CIT has confirmed that this feature was not documented in Citect for Windows versions 5.31 to 5.40 Service Pack A. The documentation will be fixed in future versions.