ISE
Schematic Overview
Using schematics for your top-level or lower-level design files allows you to have a visual representation of your design. You can use schematics for your top-level design, your lower-level design files, or both, as follows:
  •  Top-level schematic
    You can use a schematic as your top-level design and create the lower-level modules using any of the following source types: HDL files, CORE Generator™ cores, Architecture Wizard IP, or schematic files. To instantiate a lower-level module in your top-level design, you must create a schematic symbol from the lower-level module, and instantiate the schematic symbol. For information on schematic symbols, see Creating a Schematic Symbol. For more information on top-level schematics, see Creating a Top-Level Schematic.
    Note You do not need to create schematic symbols for CORE Generator cores or for Xilinx® Unified Library symbols. The CORE Generator software automatically generates schematic symbols, and library symbols are predefined. The CORE Generator software and Architecture Wizard are not supported for CPLDs.
  •  Lower-level schematic
    You can use schematics to define the lower-level modules of your design. If the top-level design file is a schematic, you must create a schematic symbol from the lower-level schematic, and then instantiate the symbol in the top-level schematic. If the top-level design file is an HDL file, you must create an HDL instantiation template from the schematic, and then instantiate the template in the top-level HDL file. For more information, see Creating a Lower-Level Schematic.
All schematics are ultimately converted to either VHDL or Verilog structural netlists before being passed on to your synthesis tool during the Synthesize process.
Note You cannot run the Schematic and Symbol Editors directly from the command line. This software must be launched from Project Navigator.
Additional Resources
Additional information is available in the following Xilinx documentation.
DocumentationTopics Covered
Schematic and Symbol Editors Help
Note In the Help Viewer, click the Synchronize TOC button Image to view all related Help topics.
Schematic and Symbol Editors software
Libraries GuidesXilinx Unified Library Symbols
See Also
Design Entry Overview
Intellectual Property and Cores Overview
Schematic to HDL Netlist Conventions

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