Employing a configurable processor within your FPGA gives you lots of options that may not have been available with a fixed microprocessor, particularly the ability to adapt to a wide variety of application requirements.
Embedded systems are very different from desktop PCs, but the underlying technology shifts are the same and follow similar growth trends. While desktop PCs are moving to 64-bit processor architectures to address growing memory requirements, embedded systems are rapidly moving to 32-bit processors for the same reason. The desktop/server computing market is consolidating around the x86 microarchitecture, and most of the innovation and differentiation is happening at the system level with dual, quad, or multicore architectures, and integrated graphic processor units and memory controllers. Similarly, embedded systems are consolidating around simple 32-bit RISC processors, while significant system-level developments such as multicore architectures, integrated peripherals, and configurable processing enable designers to adapt to rapidly changing application requirements.
According to iSuppli research reports, during 2007, the 32-bit microcontroller (MCU) market is expected to surpass the 8-bit market. As shown in Figure 1, the high-level trend is that while the 32-bit market is expected to outpace the growth of the rest of the semiconductor market, the 8-bit market has actually been shrinking for the last few years.
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The primary driver for this trend is the growing software content and complexity in embedded systems. The immediate consequence is that a wider memory bus (32 bits) is required to address larger code and data use by software programs. Unlike older microprocessors, 32-bit processors don't require memory techniques like segmentation to deal with larger memory spaces and hence make it easier to program. While 8-bit MCUs had to be programmed in difficult assembly languages to meet the small memory budgets (less than 32 kbytes), many 32-bit embedded applications can be programmed in C/C++, making embedded software developers more productive. More significantly, a large number of operating systems (real time and non-real time) have ready-made drivers and software libraries, enabling software developers to focus on their custom application development tasks.
Integration = lower prices
Smaller silicon process geometries in line with Moore's Law have brought down the cost of 32-bit embedded solutions to meet the price requirements of a broader range of applications. In addition, integrated peripherals and on-chip memory have further reduced the component and total bill-of-materials cost. By integrating peripherals optimized for vertical applications like cell phones and gaming consoles, the price of many devices has been reduced significantly, directly contributing to market growth.
Price pressure also necessitates that only a fixed combination of peripherals can be integrated into these systems, thus the peripheral mix is usually targeted to high-volume applications. However, one size doesn't always fit all, and many small, medium, and even some high-volume applications are underserved by off-the-shelf integrated solutions. As a result, designers must incorporate additional chips to expand the peripheral set, offload the processor, or add glue logic. This is where configurable processing solutions come in.
