The Practical Xilinx Designer Lab Book 1.5

Field Programmable logic devices (FPLDs) provide a complete TTL parts cabinet in a single chip. Each FPLD contains thousands of digital logic gates interconnected by internal electronic switches. The switches can be programmed at any time to create a completely different logic circuit.

This book shows the reader how to construct digital logic circuits using two types of FPLDs: field programmable gate arrays (FPGAs) and complex programmable logic devices (CPLDs). The text's philosophy is based on the idea that digital design expertise is acquired by building circuits to see how they work. Each chapter presents working examples of logic circuits which the reader can experiment with by loading them into either an FPGA or CPLD. While some theory of logic design is presented, the overall tone is more practical. It can be understood by anyone with a knowledge of binary arithmetic and elementary logic operations.

The Practical XILINX Designer Lab Book
Table of Contents

1. The Digital Design Process

Discusses the steps involved in designing a digital circuit and shows how to build it using TTL chips.

2. Programmable Logic Design Techniques

Discusses the advantages of using programmable logic and introduces the XILINX Foundation software.

3. Combinational Logic

Describes commonplace logic functions (such as encoders, decoders, multiplexers, parity generators, and adders) and shows how to implement them using ABEL, VHDL and schematic editors

4. Modular Designs and Hierarchy

Discusses the advantages of stepwise refinement and encapsulation in the design of digital circuits using parity generators and binary adders as examples.

5. Electrical Characteristics

Covers the various types of digital I/O pins, propagation delays, and power usage of programmable devices.

6. Flip-Flops

Describes how the various unclocked, clocked, and edge-triggered flip-flops operate and gives a working design for each one.

7. State Machine Design

Covers Mealy and Moore machines using examples of a counter and drink machine controller.

8. Memories

Discusses the various components of semiconductor memories and then shows how to build one using flip-flops. An example using the built-in RAM of an FPGA is also shown.

9. The GNOME Microcomputer

Covers the instructions set design and construction of a 4-bit processor in both a CPLD and FPGA. The microcomputer operation is demonstrated using a program that multiplies binary numbers.

10. The DWARF Microcomputer

Extends the GNOME microcomputer design by increasing the datapath to 8 bits and adding more addressing modes, I/O ports, subroutine stack, and interrupts.

Appendix A: Building the XS40 and XS95 Lite Boards