LogiBLOX Reference/User Guide

Preface

About This Manual

This manual describes the Xilinx^® LogiBLOX^™ program, a tool used to create high-level modules for insertion into a schematic or an HDL-based design.

Before using this manual, you should be familiar with the operations that are common to all Xilinx software tools: how to bring up the system, select a tool for use, specify operations, and manage design data. These topics are covered in the Quick Start Guide.

Other publications you can consult for related information are the Development System Reference Guide, Libraries Guide, and your third-party user guide.

You must consult The Programmable Logic Data Book for device-specific information on Xilinx device characteristics, including readback, boundary scan, configuration, length count, and debugging. The Programmable Logic Data Book is available in hard copy form and on the Xilinx web site (http://www.xilinx.com). See http://www.xilinx.com/partinfo/databook.htm for the current version of this book.

For specific design issues or problems, use the Answers Search function on the Web (http://www.xilinx.com/support/searchtd.htm) to access the following.

• Answers Database: current listing of solution records for the Xilinx software tools
  
  
• Applications Notes: descriptions of device-specific design techniques and approaches
  
  
• Data Sheets: pages from The Programmable Logic Data Book
  
  
• XCELL Journal: quarterly journals for Xilinx programmable logic users
  
  
• Expert Journals: the latest news, design tips, and patch information on the Xilinx design environment
  
  

If you cannot access the Web, you can install and access the Answers book with the DynaText online browser in the same manner as the Xilinx book collection. The Answers book includes information in the Answers Database at the time of this release.

Manual Contents

This manual covers the following topics.

• Chapter 1, “Introduction,” covers the features of LogiBLOX, the program components, the two possible design flows you can use to generate designs with LogiBLOX, and the different outputs generated by the program.
  
  
• Chapter 2, “Getting Started,” provides the basic procedures from setting up a LogiBLOX project and creating a module to placing that module in a schematic or in an HDL file.
  
  
• Chapter 3, “Understanding Attributes,” explains the major attributes that you can use to customize LogiBLOX modules.
  
  
• Chapter 4, “Module Descriptions,” describes each library module, including the input and output pins of the module and the attributes you can specify to change the functionality of the module.
  
  
• Appendix A, “LogiBLOX Versus X-BLOX/Memgen,” describes the differences between LogiBLOX and its predecessors, X-BLOX and Memgen.
  
  

Conventions

Typographical

This manual uses the following conventions. An example illustrates each convention.

• Courier font indicates messages, prompts, and program files that the system displays.
  
  speed grade: -100
  
  
• Courier bold indicates literal commands that you enter in a syntactical statement. However, braces “{ }” in Courier bold are not literal and square brackets “[ ]” in Courier bold are literal only in the case of bus specifications, such as bus [7:0].
  
  rpt_del_net=
  
  Courier bold also indicates commands that you select from a menu.
  
  File Open
  
  
• Italic font denotes the following items.
  
  
  • Variables in a syntax statement for which you must supply values
    
    edif2ngd design_name
    
    
  • References to other manuals
    
    See the Development System Reference Guide for more information.
    
    
  • Emphasis in text
    
    If a wire is drawn so that it overlaps the pin of a symbol, the two nets are not connected.
    
    
• Square brackets “[ ]” indicate an optional entry or parameter. However, in bus specifications, such as bus [7:0], they are required.
  
  edif2ngd [option_name] design_name
  
  Square brackets also enclose footnotes in tables that are printed out as hardcopy in DynaText^®.
  
  
• Braces “{ }” enclose a list of items from which you must choose one or more.
  
  lowpwr ={on|off}
  
  
• A vertical bar “|” separates items in a list of choices.
  
  lowpwr ={on|off}
  
  
• A vertical ellipsis indicates repetitive material that has been omitted.
  
  IOB #1: Name = QOUT'
  IOB #2: Name = CLKIN'
  .
  .
  .
  
  
• A horizontal ellipsis “. . .” indicates that an item can be repeated one or more times.
  
  allow block block_name loc1 loc2 ... locn;
  
  

Online Document

Xilinx has created several conventions for use within the DynaText online documents.

• Red-underlined text indicates an interbook link, which is a cross-reference to another book. Click the red-underlined text to open the specified cross-reference.
  
  
• Blue-underlined text indicates an intrabook link, which is a cross-reference within a book. Click the blue-underlined text to open the specified cross-reference.
  
  
  
  
• There are several types of icons.
  
  Iconized figures are identified by the figure icon.
  
  
  
  Iconized tables are identified by the table icon.
  
  
  
  The Copyright icon displays in the upper left corner on the first page of every Xilinx online document.
  
  
  
  The DynaText footnote icon displays next to the footnoted text.
  
  
  
  Double-click these icons to display figures, tables, copyright information, or footnotes in a separate window.
  
  
• Inline figures display within the text of a document. You can display these figures in a separate window by clicking the figure.