Testing DSP Performance with LabVIEW DSP Test Integration Toolkit

Author(s):
Andres Mellik - Tallinn Technical University

Industry:
Electromechanics/ Electrotechnics, University/Education, Machines/Mechanics, Industrial Controls/ Devices/ Systems

Products:
LabVIEW

The Challenge:
Examining how to make the test development and operation of DSP performance testing easier and compare the actual DSP performance with a DSP model.

The Solution:
Using the LabVIEW DSP Test Integration Toolkit and the LabVIEW Simulation Interface Toolkit to visualize and test DSP performance.

At ALaRI, our main research areas are hardware and software design of embedded microsystems, with specific relation to high-performance applications. We aim to create a bridge between software technologies and electronic engineering by exploring cutting-edge topics and addressing our research toward pragmatic industrial problems coming from the "real-world".

DSP Testing Process
The code running on a DSP is compared to a Simulink model executing in parallel on the PC. Using the LabVIEW Simulation Interface Toolkit, we compiled the Simulink model into a dynamic link library (DLL) and accessed the DLL in the LabVIEW graphical development environment. We interacted with the DSP using the LabVIEW DSP Test Integration Toolkit for TI DSP. This toolkit automates the IDE functions of Texas Instruments Code Composer Studio (CCS) and communicates directly to a DSP development board through the Real-Time Data Exchange (RTDX) interface.

We compared the outputs of the Simulink model and the actual DSP using the test module and exposed any differences in the behavior. These differences are derived from the code optimization for the C++ code generated by Real-Time Workshop in Simulink, the DSP code, and the specific target architecture.

Our goal was to increase automation in DSP testing systems using RTDX and dedicated measurement and data acquisition software – LabVIEW 6.1 with add-ons.

By combining the RTDX and LabVIEW 6.1 with add-ons, we hoped to achieve a noticeable reduction in test development and operation. When using a common DSP, such as a TI 6711-series, and algorithm(s) for a specific application, the present system eases the process. In case of custom DSPs, the testing cycle can account for a large part of the whole production cycle.

We achieved one of our primary goals of using dedicated tools from leading vendors in developing the application. We applied the LabVIEW DSP Test Integration Toolkit for TI DSP and the LabVIEW Simulation Interface Toolkit in accordance with their domain.
By developing all parts of the system in LabVIEW, we utilized the benefits of developing a fast data acquisition and measurement system.

Creating a Sample Application
We chose an LMS algorithm for adaptive noise cancellation as our system to integrate MATLAB, TI Code Composer Studio, and LabVIEW. After completing our model, we used The MathWorks Real-Time Workshop to generate the DLL we accessed in LabVIEW.

Communication with the DSP development board is handled through RTDX. We used the parallel port as the actual interface to the DSP board in this implementation, but we have proposed the use of JTAG for future developments.We can use the test module to compare the two filtered outputs for possible differences and generate a results file, database entry, or graph.

For more information, contact:
Andres Mellik
Tallinn Technical University
Address: Luha 14-1, Tallinn 10129, Estonia
Tel: +372 56 58 388
E-Mail: amellik@yahoo.com

Browse All Case Studies »