Indian Journal of Science and Technology

Abstract

Objective: Field Programmable Gate Arrays (FPGAs) are often used to accelerate hardware systems by implementing algorithms on hardware. This paper presents the design and implementation of a fully pipelined single-precision FloatingPoint Unit (FPU) on a Spartan-6 FPGA chip. Methods: This paper presents a high-speed, modular design for improving the performance of such applications. While the proposed design is capable of performing basic arithmetic operations and square-root extraction, its modularity enables designers to add more functionality easily; or remove modules that they deem unnecessary for a particular application. Findings: The investigation shows that the adder and multiplier modules can be clocked at over 300 MHz and the top-module at over 200 MHz High operating frequencies were achieved by precomputing possible values in earlier pipelining stages, then correcting results in later pipelining stages. It was also found that splitting longer operations in the critical path is a better alternative than processing the whole operation at once. Limiting “Max_Fanout”, an attribute provided by Xilinx XST tool, proved valuable in reducing delays on overloaded nets. Applications: This FPU would be a worthwhile addition as a floating-point extension in fixed-point processors for applications such as spectrum analyzers, 3D graphics, and audio processing units.
Keywords: DSP48A1Multiplier, FPU, FPGA, High-speed Pipeline, Out-of-order Processing, Non-restoring Algorithm, Spartan-6, Single-Precision,