How do I Access Internal Channels on my DAQ Device using DAQmx?Primary Software: Primary Software Version: 1.0 Primary Software Fixed Version: N/A Secondary Software: N/A
Problem: How do I access the internal channels for my DAQ device using the DAQmx API? Solution: By default, DAQmx Physical Channel controls and constants filter out internal channels for DAQ devices, as well as things like invalid I/O types. Channels labeled "internal" are typically used for self-diagnostics and self-calibration, and thus are hidden by default to avoid overcomplicating DAQmx configuration for newer programmers and end-users. Note: A list of internal channels for your device can be found in DAQmx Help: Internal Channels. Also note that for S Series devices, there are additional steps necessary to correctly access internal channels, which are listed in the DAQmx Help documentation mentioned above. To view these hidden channels, you'll need to modify the default I/O Name Filtering options for that particular control or constant. Complete the following steps to Enable Internal Channels: LabVIEW LabWindows/CVI .NET API LabVIEW:
Note: In addition to showing internal channels, you can also customize things such as I/O Type and even limit the options to a particular device to prevent users from inputting invalid channels for a control. LabWindows/CVI:
.NET API: In the .NET API, you are required to specify the access level of the GetPhysicalChannels method during configuration of the method. Specify Internal or All instead of External , and you will see the additional channels. See the example below:
Related Links: KnowledgeBase KB 35TGB1VM: NI-DAQmx Internal Channels for Self-Diagnostics and Self-Calibration KnowledgeBase KB 3G0G2IZH: Enabling the Advanced Channels on a DAQmx Terminal Control/Constant KnowledgeBase KB 533A1Q9N: Can I Create a Global Virtual Channel Out of an Internal NI-DAQmx Channel? White Paper: Learn 10 Functions in NI-DAQmx and Handle 80 Percent of Your Data Acquisition Applications KnowledgeBase KB 25S9MQED: Archived: Using Internal Analog Input Channels in Traditional NI-DAQ (Legacy) Attachments:
Report Date: 02/04/2010 Last Updated: 01/25/2017 Document ID: 563B1D3A |