Pico Communications E-14 - Manual (Page 7)

E‐14 Hardware Reference Manual www.picocomputing.com Pico Computing, Inc.
7
Field Programmable Gate Array
The core of the Pico E‐14 is a high performance Virtex‐4 FPGA. Included in the FPGA are the FPGA
Fabric, a Power‐PC ™ processor, ultra high‐speed DSP slices and DDR2 RAM.
FPGA Fabric:
The “Fabric” of an FPGA comprises an array of logic elements that can be connected in virtually
unlimited patterns. These patterns of logic elements can be used to perform basic mathematical
functions such as addition and subtraction, or can be grouped together to perform complex functions
like Fast Fourier Transforms. Logic elements can even be connected to create a custom soft processor.
The advantage of the FPGA is that the internal logic can be optimized for a specific application. FPGAs
are also able to execute operations in parallel, not being limited by sequential execution like a
traditional processor. FPGA operations can be executed in a parallel, pipelined or even an
asynchronous manner. The FPGA allows incredible application speed with very low power
consumption. Your imagination is really the limit.
DSP Slice:
Embedded within the FPGA are special areas that are designed to facilitate high speed “digital signal
processing.” These areas are called DSP slices. The DSP slice can be configured in a variety of different
ways. For example one DSP slice can be configured to be one tap of an FIR filter. DSP slices are fully
pipelined and feature incredible speed. When configured for FIR filtering the DSP slice has a
guaranteed performance of 500MHz with a latency of one cycle. An 18x18 multiply and accumulate
also runs at 250MHz with a latency of two cycles. Smaller data widths allow higher clock speeds.
FPGA Resources:
Free FPGA Cores www.opencores.org
Virtex‐4 Website www.xilinx.com/virtex4