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

When TrnGetBufValue() encounters an invalid or gated value, spurious hardware alarms can be generated. 

TrnGetBufValue() now returns the standard Invalid or Gated values, and no hardware alarm is raised. The caller of these functions may need to check the returned value by calling TrnIsValidValue(). Please refer to the online help for TrnIsValidValue() for further information.

CIT has confirmed this to be a problem in Citect for Windows versions 5.31 to 5.40 Service Pack A. This problem has been fixed in version 5.40 Service pack B.