Digital Signal Processing Implementation Using the TMS320C6000 DSP Platform

• Authors: Naim Dahnoun
• Venue: Digital Signal Processing Implementation Using the TMS320C6000 DSP Platform
• Year: 2000

From the Book:PREFACE: Preface Digital signal processing techniques are now so powerful that sometimes it is extremely difficult, if not impossible, for analogue signal processing to achieve the same or closer performance. Added to this, digital signal processors are very affordable and include good development tools and support. This is sufficient to explain the growing number of areas of application for DSP, including motor drives, communications, biomedical instrumentation and automotive applications. Having dealt for some time with undergraduate and postgraduate students, researchers and digital signal processor users in general, I have found that first-time users of DSP find a barrier obstructing them in progressing from theory to the full implementation of algorithms. When it comes to implementing an algorithm many questions arise, questions such as: Which processor to use - fixed or floating point? Which manufacturer to choose? Which application hardware to use? How many I/O interfaces are needed and how fast should they be? When these questions are answered, more questions arise regarding the implementation on the specific processor and hardware selected. In this book, use of the TMS320C6000 will be justified, and the hardware and complete implementation of selected algorithms will be dealt with in detail. Material used for the teaching of undergraduate and postgraduate students, along with laboratory experiments, are used to demonstrate and simplify the transition from theory to the full implementation on the TMS320C6201 processor. This book is divided into nine chapters. Chapters2and 3 are very important and it is advisable that they are well understood before progressing onto subsequent chapters. Chapter 1 Introduction This introductory chapter provides the reader with general knowledge on general-purpose DSP processors and also provides an up-to-date TMS320 roadmap showing the evolution of Texas Instruments' DSP chips in terms of processing power. Chapter 2 The TMS320C62xxlC67xx architecture The objective of this chapter is to provide a comprehensive description of the 'C6x architecture. This includes a detailed description of the Central Processing Unit (CPU) and program control along with an overview of the memory organisation, serial ports, boot function and internal timer. Chapter 3 Software development tools and TMS32OC6201 EVM overview This chapter is divided into three main parts. The first part describes the software development tools, the second part describes the Evaluation Module (EVM) and, finally, the third part describes the codec, and use of interrupts along with some useful programs for testing the TMS320C6201 EVM. Chapter 4 Software optimisation To introduce the need for code optimisation, this chapter starts by developing the concept of pipelining. Since the TMS320C62xx and the TMS320C67xx each have eight units, which are dedicated to different operations, and since different instructions can have different latencies, the programmer or the tools are left with the burden of scheduling the code. Backed by examples, this chapter explains the different techniques used to optimise DSP code on these processors. Chapter 5 Finite Impulse Response (FIR) filter implementation The purpose of this chapter is twofold. Primarily, it shows how to design an FIR filter and implement it on the TMS320C62xx processor, and secondly, it shows how to optimise the code as discussed in Chapter 4. This chapter discusses the interface between C and assembly, how to use intrinsics, and how to put into practice material that has been covered in the previous chapters. Chapter 6 Infinite Impulse Response (IIR) filter implementation This chapter introduces the IIR filters and describes two popular design methods, that is the bilinear and the impulse invariant methods. Step by step, this chapter shows the procedures necessary to implement typical IIR filters specified by their transfer functions. Finally, this chapter provides complete implementation of an IIR filter in C language, assembly and linear assembly, and shows how to interface C with linear assembly. Chapter 7 Adaptive filter implementation This chapter starts by introducing the need for an adaptive filter in communications. It then shows how to calculate the filter coefficients using the Mean Square Error (MSE) criterion, exposes the Least Mean Square (LMS) algorithm and, finally, shows how the LMS algorithm is implemented in both C and assembly. Chapter 8 Goertzel algorithm implementation This chapter deals with Dual Tone Multi-Frequency (DTMF) detection and provides a practical example of the Goertzel algorithm. This chapter also shows how to produce optimised code by the pen and paper method, describes linear assembly and demonstrates how to program the Direct Memory Access (DMA). Chapter 9 Implementation of the Discrete Cosine Transform This chapter starts by introducing the need for video compression to reduce the channel bandwidth requirement, then explains the Joint Photographic Experts Group (JPEG) image codec. This includes a detailed discussion and the implementation of the Discrete Cosine Transform (DCT) and Inverse Discrete Cosine Transform (IDCT) and concentrates on their optimisation. An explanation of the PC-DSP communication via the PCI bus is also provided. Software The accompanying CD includes all the programs used in this book. To help the reader in locating or viewing the files, an Index.htm file has been included. The files are in separate directories corresponding to each chapter. Some directories are further divided in sub-directories to separate different implementations. Batch files for compiling, assembling and linking these programs are included. All the files have been tested (the environment may need to be modified: see env.bat file). Software using Code Composer Studio environment is also provided. Software updates including code running on the TMS320C6211 DSK can be obtained from the Publisher. Acknowledgements As you can imagine, it is hard to produce any textbook on state-of-the-art technology, especially when the time factor is playing against you. However, with the first very encouraging comments from the five anonymous reviewers, my motivation for writing this book surged, and therefore I would like to thank them for their constructive comments. Due to the unfamiliarity with this processor, it was difficult to share ideas with other users. But with Tuan-Kiang Chiew, Kwee-Tong Heng and Michael Hart many problems were solved and many grey areas were clarified; I extend to them special thanks. I am indebted to Robert Owen, Hans Peter Blaettel, Gene Frantz, Neville Bulsara, Greg Peake, Helga and Graham Stevenson and Maria Ho of Texas Instruments for their encouragement, continuous help and support. I owe my thanks to Professor Barrie Jones, Professor David Evans, Dr. John Fothergill and Fernando Schlindwein from Leicester University for their encouragement, and Dr Anthony Brooms from Oxford University and Dr Mark Yoder from the Rose-Hulman Institute of Technology, USA, for reviewing the material. My thanks to all of my colleagues at the Department of Engineering at Bristol University and to all of our students, in particular Khaled, Fernando, Mohamed, Samir, Chris, Shirley and Julian. Also I would like to thank Cornelius Kellerhoff, European DSP Business Development Consultant, Paul Coulton, Communications Research Centre, Lancaster University, and Mariusz Jankowski, University of Southern Maine, for their valuable technical reviews. I thank my parents, family and friends for their support and encouragement. Finally, many thanks to Karen Sutherland, Julie Knight and all of the Pearson Education and Prentice Hall team who were very kind, supportive and encouraging. N. Dahnoun [e-mail]