EGR426 W’10Laboratory #1Tutorial on Xilinx ISE 10.1Objectives- To become familiar with using Xilinx ISE to draw schematic representations of PLD circuits- To become familiar with using Xilinx ISE to conduct graphical waveform simulations of PLD circuits- To become familiar with using Xilinx ISE to write HDL representations of PLD circuits- To become familiar with using Xilinx ISE to write HDL testbench simulations of PLD circuits- To become familiar with downloading PLD circuits to the Nexys development boardIntroduction“There is more than one way to do it” (TIMTOWTDI, usually pronounced "Tim Toady") is a Perl motto. The language was designed with this idea in mind, so that it "doesn't try to tell the programmer how to program". This makes it easy to write extremely messy programs, but, as proponents of this motto argue, it also makes it easy to write beautiful and concise ones.The Zen of Python has a principle which is the exact opposite of TIMTOWTDI: "There shouldbe one—and preferably only one—obvious way to do it."1In designing programmable logic, and in the tools used to do so, there is definitely more than one way todo it.Part I – Drawing SchematicsThe Xilinx Integrated Software Environment (ISE) allows users to design circuits for Xilinx FPGA’s andCPLD’s. It involves the use of Project Navigator, a user interface that helps users manage the entiredesign process including design entry, simulation, synthesis, implementation and finally downloading thedesign onto an FPGA or CPLD. 1. Start ISE from the Start menu by selecting Start -> Programs -> Xilinx ISE Design Suite 10.1 ->ISE -> Project Navigator. The ISE Project Navigator opens as shown in Figure 1. The ProjectNavigator lets you manage the sources and processes in your ISE project. 1 Description reprinted from WikipediaEGR426 W’10 2Figure 1: Launching ISE Project Navigator2. The next step is to create a new ISE project. To create a new project for this tutorial: Select File -> New Project. The New Project Wizard appears as shown in Figure 2. First, enter a Project Location (directory path) for the new project. Choose a location on your USBdrive since files stored on laboratory computers do not persist once the computer shuts down.NOTE: DO NOT EVER SPECIFY A DIRECTORY OR FILENAME WITH SPACES. Thiswill cause Xilinx to mysteriously fail on certain operations. Type counter in the Project Name field. When you type counter in the Project Name field, acounter subdirectory is created automatically in the directory path you selected. Select Schematic in the Top-Level Source Type list, indicating that the top-level file in yourproject will be a schematic rather than another type, such as HDL, EDIF or NGC/NGO. ClickNext to go to the Device Properties windowCopyright 2010 GVSU School of EngineeringEGR426 W’10 3Figure 2: Creating a new project3. In the Device Properties window, you will be selecting your Target device, Simulator tool, Synthesistool and Hardware language in which you will be writing your design code. Figure 3 shows theselections you need to make. NOTE: If you purchased the Nexys board with the -1200 option, youshould select the XC3S1200E device instead of the XC3S500E device. All other fields can stay thesame.Figure 3: Target Device and Tool SelectionCopyright 2010 GVSU School of EngineeringEGR426 W’10 44. Click Next three times and you will reach the Project Summary window. This window gives you anoverview of your project created so far. Click on Finish and your project is created as shown in Figure4. Verify that the project name is counter.ise (shown as the last component in the title bar of theapplication). You can also verify by going to the location where you created the project and double-clicking on the folder named counter.Figure 4: Successful creation of project5. Now you will create a top level schematic for your design. In the Sources window, right click onxc3s500e-4fg320 and select New Source. A New Source Wizard window appears as shown in Figure5. Select Schematic and enter counter under file name. Make sure the “Add to project” checkbox ischecked.Figure 5: Creation of a schematic source file6. Click Next two times followed by Finish to create the counter.sch file under the project folder. Figure6 shows the final layout of the project after the source file is created. If you don’t see the schematic,Copyright 2010 GVSU School of EngineeringEGR426 W’10 5you may see a Design Summary. Click on the “counter.sch” tab at the bottom of the main designwindow to see the schematic.Figure 6: Project Navigator showing top-level schematic7. The Sources window at the top-left should have the Symbols tab selected (there are 5 tabs at thebottom of the window). From this tab, you can select schematic symbols to add to the schematic.From the Categories listbox, select Counter. Then, from the Symbols listbox, select “cb2ce”. Moveyour cursor to the main schematic window on the right and you will see a schematic symbol attachedto the cursor. Left-click to place the symbol on the schematic. Press ESCAPE to detach the symbolfrom the cursor, and then press the F8 key several times to zoom in on the symbol you placed. Theresult should be as shown in Figure 7. Copyright 2010 GVSU School of EngineeringEGR426 W’10 6Figure 7: CB2CE symbol added to schematic8. To enable the counter to count, we have to tie the CLR input low, since this is an active-highasynchronous clear input. From the Categories listbox on the left, select General, and from theSymbols listbox select ‘gnd’. Place a ground symbol on the schematic below the connection point ofthe CLR pin (look forward to Figure 8 for reference).9. The CE clock-enable pin is active-high. To allow the counter to count, we have to tie this pin high.From the Categories listbox, select the <-All Symbols-> choice right at the top, and type ‘vcc’ in theSymbol Name Filter textbox (a quicker way to add symbols when you already know the name). Clickon the ‘vcc’ symbol name in the Symbols listbox and use the cursor to place a VCC symbol above theCE pin on the schematic.10. Press Ctrl-W to start drawing wires, then click on the connection point of the CE pin (the smallsquare). Draw a wire ending at the connection point of the VCC symbol. Similarly, connect the CLRpin and GND symbol together. The result should be as shown in Figure 8.Copyright