Historically, ARM has found success in low-cost, high-volume applications by offering simple, small, general-purpose processor cores. Given that focus, some may be surprised that ARM has decided to include extensive DSP-oriented instructions as part of its baseline architecture. To many, though, this is just one more sign that digital signal processing is becoming an essential part of many embedded processor applications. In ARM's view, it no longer makes sense to offer processors without DSP features.

As the performance of general-purpose processors increases, and as more general-purpose processors add DSP-oriented features, there is less need for specialized DSPs. Even without DSP-specific features, many general-purpose processors can handle low- to moderate-performance DSP applications. Thus, the choice of a processor for a low-cost DSP application is increasingly decided by factors other than performance. The breadth and quality of development tools and third-party software are often critical in determining the success of a system design.

Today, general-purpose processors often offer superior development tools and application software, particularly for non-DSP functionality. DSPs, in contrast, typically provide superior development support for DSP-intensive tasks. Vendors of both types of processors face challenges here. For general-purpose processor vendors, it isn't enough to provide processors with DSP capabilities; those capabilities must be supported by solid, DSP-oriented application development support. For DSP processor vendors, it's time to recognize that general-purpose processors are mounting serious competition. Competing against them requires first-class tools and developer support beyond the realm of traditional DSP apps.

Five years from now, the success of a processor in many DSP applications may have less to do with how many multiply-accumulate operations it can perform in parallel, and more to do with whether it can boot Linux.

Jeff Bier is the general manager of Berkeley Design Technology Inc. ( www.bdti.com), a dsp technology analysis and software development company. Kenton Williston of BDTI contributed to this column.