Sanjay Challa, National Instruments -April 10, 2013

With the explosion of embedded devices in the past few decades, many improvements have been made in both the hardware components and software tools. Despite this innovation and growth, however, traditional embedded-system design approaches have evolved little if at all and are increasingly proving to be a hurdle. Given the increasingly rapid growth of new standards and protocols as well as increasing pressure on design teams to deliver to market more quickly, embedded-system design is due for a disruptive paradigm change.

With the accelerating growth of advances in hardware technologies and software tools, the challenge posed by integration is set to rise. This challenge, if unaddressed, will result in more expensive end products and can prevent experimentation, growth, and delivery of more innovative designs to the marketplace.

Standard embedded architecture

In the general computing marketplace, standardization has resulted in more robust operating systems, more refined end applications, and advances in the underlying hardware components. The lesson learned is that time saved in avoiding the integration effort of custom hardware architectures and associated software components results in better end solutions, which are delivered to market faster.

For the embedded space, a corresponding standard architecture needs to be flexible enough to adapt to diverse use cases while providing an avenue for updates. Given these constraints, the most robust architecture for standardization in the embedded design space is a microprocessor and an FPGA working alongside each other as a single unit (Figure A). Together, these two elements enable substantial flexibility in designs.



Figure A In this standard hardware architecture, the combination of a processor and an FPGA enables flexibility while making it possible for standardization that can utilize higher-level tools to make substantial gains in the design workflow. The processor makes it possible to reuse existing code libraries, while the FPGA allows for the flexible implementation of custom algorithms.

FPGAs offer the benefits of hardware determinism and reliability without the up-front cost and rigidity of ASIC design. Additionally, the ability to load new logic and redefine the connections in the FPGA fabric makes it possible for designers to future-proof designs and benefit from more robust updates without requiring any substantial modifications to hardware.

The combination of processors and FPGAs in embedded-system design is growing in many industries. Embedded-systems developers are using designs based on several processors and FPGAs. The FPGAs are used to take accurate, high-speed measurements or run time-critical algorithms. Meanwhile, the processors run a real-time operating system to handle lower-frequency control loops or provide Ethernet communication to other distributed nodes and facilitate remote data access, system management, and diagnostics.

Higher-level tools

A key benefit of a standard architecture is that more capable and optimized high-level tools can be developed and used for design. Higher-level tools make it possible for domain experts to be more closely involved in embedded- system design with smaller and more efficient design teams. As a result, more complex products can be pushed to market sooner with smaller design teams.

General-purpose computing provides evidence for the efficiencies that can be gained in application development with higher-level design tools and languages. Unsurprisingly, the embedded marketplace has started to witness the growth of higher-level design tools, including the Xilinx AutoESL C-to-Gates high-level synthesis tool, Mentor Graphics Catapult C Synthesis tool, and NI LabVIEW ultimate system-design software.

EDN