Digilent Nexys 3 - User Manual

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Nexys 3™ FPGA Board Reference Manual
Revised April 11, 2016
This manual applies to the Nexys 3 rev. B
DOC#: 502-182
Copyright Digilent, Inc. All rights reserved.
Other product and company names mentioned may be trademarks of their respective owners.
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Overview
The Nexys 3 is a complete, ready-to-use digital circuit development platform based on the Xilinx Spartan-6 LX16
FPGA. The Spartan-6 is optimized for high performance logic, and offers more than 50% higher capacity, higher
performance, and more resources as compared to the Nexys 2's Spartan-3 500E FPGA.
In addition to the Spartan-6 FPGA, the Nexys 3 offers an improved collection of peripherals including 32Mbytes of
Micron's latest Phase Change nonvolatile memory, a 10/100 Ethernet PHY, 16Mbytes of Cellular RAM, a USB-
UART port, a USB host port for mice and keyboards, and an improved high-speed expansion connector. The large
FPGA and broad set of peripherals make the Nexys 3 board an ideal host for a wide range of digital systems,
including embedded processor designs based on Xilinx's MicroBlaze.
Nexys 3 is compatible with all Xilinx CAD tools, including ChipScope, EDK, and the free WebPack. The Nexys 3 uses
Digilent's newest Adept USB2 system that offers FPGA and ROM programming, automated board tests, virtual I/O,
and simplified user-data transfer facilities.
A comprehensive collection of board support IP and reference designs, and a large collection of add-on boards are
available on the Digilent website. Please see the Nexys 3 page at www.digilentinc.com for more information.
 Xilinx Spartan-6 LX16 FPGA in a 324-pin BGA
package
 16Mbyte Cellular RAM (x16)
 16Mbytes SPI (quad mode) PCM non-volatile
memory
 16Mbytes parallel PCM non-volatile memory
 10/100 Ethernet PHY
 On-board USB2 port for programming & data
xfer
 USB-UART and USB-HID port (for
mouse/keyboard)
 8-bit VGA port
 100MHz CMOS oscillator
 72 I/Os routed to expansion connectors
 GPIO includes 8 LEDs, 5 buttons,8 slide
switches and 4-digit seven-segment display
 USB2 programming cable included
Features include:

Summary

Overview

Configuration

Adept System

Details the Digilent Adept high-speed USB2 system for programming, testing, and virtual I/O.

Programming Interface

Guides users on setting up the board and software to program the FPGA via the Adept USB port.

Memory Interface

Describes transferring configuration files and user data to on-board PCM devices and RAM.

Test Interface

Provides methods to verify the board's hardware circuits and interfaces, including memory and peripherals.

Register I;O

Enables moving small amounts of data into/out of specific FPGA registers via an EPP-style interface.

File I;O

Allows transferring files between a PC and the Nexys 3 FPGA, including streaming data to/from registers.

I;O Expand

Facilitates additional simple I/O using an IP block for virtual devices like LEDs, switches, and buttons.

Power Supplies

Memory

Ethernet PHY

Oscillators;Clocks

USB-UART Bridge (Serial Port)

USB HID Host

HID Controller

Explains accessing the USB host controller using EDK or a state machine for PS/2 communication.

Keyboard

Describes PS/2 keyboard scan codes, commands, and data transfer protocols.

Mouse

Explains mouse data transmission, including movement data, button presses, and status bytes.

VGA Port

VGA System Timing

Specifies VGA signal timings for a 640x480 mode display, detailing sync pulses and pixel data.

Basic I;O

Seven-Segment Display

Explains the four-digit common anode seven-segment LED display and its multiplexed operation.

Expansion Connectors

VHDC Connector

Details the 68-pin VHDC connector for high-speed/parallel I/O, including pinout and power options.

Pmod Ports

Explains the 2x6 Pmod ports for connecting accessory boards with logic signals and power.

Built-In Self Test

Digilent Nexys 3 Specifications

General

Brand	Digilent
Model	Nexys 3
Category	Motherboard
Language	English