DSP Communication Using RTDX

This Tutorial explains how to use RTDX and the LabVIEW DSP Test Integration Toolkit for TI DSP to communicate to DSP code.

Note: This toolkit is no longer officially supported by NI, but you can download the VIs that were included in this toolkit.

RTDX Basics

Real-Time Data Exchange (RTDX), a technology developed by Texas instruments, is a communication protocol that establishes data pipes to send and receive data to and from a DSP device while code is running. This protocol allows you to communicate directly to DSP code in real-time without interrupting the execution of code and thereby provides engineers better feedback on how code performs, exposing flaws early in the design process.

RTDX channels must be implemented into code using Code Composer Studio (CCS). Once the channels are implemented, you can use the RTDX VIs with the DSP Test Integration Toolkit to communicate with the DSP device. The RTDX tools for LabVIEW allow you to write scalars or arrays of integers (8, 16, and 32-bit) and floating-point numbers (single and double precision) to the DSP device. RTDX read VIs also give you access to set a timeout value--the default is 2 seconds. Just like in regular LabVIEW programming, you should use error clusters to control the order of program execution.

Writing Data to an RTDX Channel

To write data to an RTDX channel, you must know the RTDX channel name that you configured in the CCS source code. When you wire the channel name and data into the write VIs, LabVIEW sends the data directly to the RTDX channel. The context help for the CCS RTDX Write Array DBL VI is shown in Figure 1.
To read from an RTDX channel, just like when writing to an RTDX Channel, you must know the RTDX channel name that you implemented in your CCS source code. After you wire the channel name and timeout value (whose default is 2 seconds) to the VI, LabVIEW receives the data and outputs the data available for the VI with the data output of the VI. The context help for the CCS RTDX Read Array DBL VI is shown in Figure 2.
Related Links:
Continuously Reading to and Writing from an RTDX Channel
More Tutorials and Example Code

Reader Comments | Submit a comment »

OK
Tutorial doesn't give an indepth knowledge of how to configure the channels in CCS settings
- May 24, 2007