Xilinx CPLD schematic libraries guide

When you get your CPLD development board, you’ll want to start coding! Programs for Xilinx CPLDs are most commonly written in Verilog or VHDL, and you will find examples on our CPLD page. A third way which is usually easier for beginners is schematic entry which you can do in the free Xilinx ISE WebPack.

Schematic programs are written using logic symbols contained in either the standard Xilinx library or imported from other sources. Symbols are linked together and connected to I/O pins to makeup your project inside the device.

Xilinx has published a massive (668 page PDF) CPLD Libraries Guide. This document is a treasure trove of information regarding every possible logic symbol contained in the ISE’s library. Each symbol appears with its name, schematic graphic, description of purpose and usage, and a logic table where applicable. Whether you’re familiar with logic symbols and their operation or are just getting started, you’ll find this to be a valuable reference tool.

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  1. Ian, BTW there is an apnote in the guide on “A Low-Power IDE Controller Design Using a CoolRunner-II CPLD” page 235.

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