Owning Palette: Advanced TDMS VIs and Functions
Requires: Base Development System (Windows). This topic might not match its corresponding palette in LabVIEW depending on your operating system, licensed product(s), and target.
Use the TDMS Advanced Data Reference I/O functions to interact with data that is owned by a component external to LabVIEW, such as the direct memory access (DMA) buffer of a device driver that controls a data-streaming device. You can use these functions to asynchronously write data from the DMA buffer of a device driver to .tdms files without needing to copy the data into a LabVIEW array first. You also can use these functions to asynchronously read data from .tdms files and place the data directly into the DMA buffer.
| Note To use the TDMS Advanced Data Reference I/O functions, you must set the enable asynchronous? input of the TDMS Advanced Open function to TRUE. |
| Palette Object | Description |
|---|---|
| TDMS Advanced Asynchronous Read (Data Ref) | Reads data from the specified .tdms file asynchronously and stores the data in the memory of a component external to LabVIEW. Use the data reference input of this function to specify the location of the external memory, such as a region of a DMA buffer owned by a device driver. |
| TDMS Advanced Asynchronous Write (Data Ref) | Writes data referenced by the data reference input to the specified .tdms file asynchronously. The data reference input typically refers to a portion of data owned by a component external to LabVIEW, such as a region of a DMA buffer that contains data you want to write to the .tdms file. |
| TDMS Configure Asynchronous Reads (Data Ref) | Configures the maximum number of asynchronous reads, total amount of data to read, and the timeout value for the asynchronous reads. The timeout value applies to all subsequent asynchronous reads. You must use this function to configure the asynchronous reads before using the TDMS Advanced Asynchronous Read (Data Ref) function. |
| TDMS Configure Asynchronous Writes (Data Ref) | Configures the maximum number of asynchronous writes and the timeout value. The timeout value applies to all subsequent asynchronous writes. You must use this function to configure the asynchronous writes before using the TDMS Advanced Asynchronous Write (Data Ref) function. |
| TDMS Get Asynchronous Read Status (Data Ref) | Returns the number of pending asynchronous reads issued by the TDMS Advanced Asynchronous Read (Data Ref) function. |
| TDMS Get Asynchronous Write Status (Data Ref) | Returns the number of pending asynchronous writes issued by the TDMS Advanced Asynchronous Write (Data Ref) function. |