When using a RIO controller in Scan or Hybrid Mode, you can access I/O Variables normally (Scanned Access), or using Direct Access. NI has discovered an issue with an internal component of Scan Mode that can cause write operations to output channels to occasionally fail to update the associated hardware line when using Direct Access.
This only affects a subset of RIO users. In order to potentially see this behavior, you must be both:
This patch updates a component distributed by CompactRIO Device Drivers 16.0.0 or 16.1.0. You must have at least one of these products installed before you can apply this patch. Refer to the corresponding readme for system requirements and supported operating systems: Downloads: NI CompactRIO 16.0.
After you have CompactRIO 16.0.0 or 16.1.0 installed, NI Update Service will allow you to download and install the 16.1.1 patch. The patch is also available from ni.com/downloads.
Once this patch is installed on the development computer, you will need to also install it to your RIO controller. To do so:
Continue through the wizard to install NI-RIO IO Scan 16.1.1 to the controller. Once this has finished, the fix will be live. The fix also includes a new warning (error code 65734) that will be thrown when using a single hardware line in a program with Scanned Access and Direct Access. This warning will also be populated as a minor Scan Engine fault.