Configurable processors: a new era in chip design

Over the past few decades, the microprocessor has emerged as a fixed, stand-alone, reusable block created by highly skilled specialists. Because developing good, efficient microprocessor architectures can take years, many designers have come to regard them as monolithic entities subject to change only over long time periods and after careful consideration by an anointed few. However, the rise of application-specific integrated circuit and system-on-chip (SoC) manufacturing technologies in the 1990s has laid the groundwork for a new, fourth era - that of post-RISC, configurable processors. Configurable processors enable system-on-chip designers to leverage the benefits of nanometer silicon lithography with relatively little manual effort. These processors can achieve much higher performance than processors with conventional fixed-instruction-set architectures through the addition of custom-tailored execution units, registers, and register files as well as specialized communication interface ports.