Downloading a bit stream to the board

These instructions assume that you have created or obtained a bit file (.bit extension). They take you through the use of iMPACT to download this file to the Spartan 3E FPGA on the BASYS Board.

1. Plug in the 5v power supply of the Pegasus board. The green LED (LD8) near the power connector will turn on. Make sure you have the right plug!

2. Without using the Project Navigator, from the Start menu select Programs->Xilinx ISE 9.2i->Accessories->iMPACT.

3. After a few seconds you should have the windows below.

4. Select Cancel in the iMPACT Project window.

5. From the Edit menu in the iMPACT window, select Launch Wizard as shown below.

6. In the window below leave all the options as they are and click on Finish and the program will talk to the Pegasus board to find out what devices it has.

7. iMPACT should report (see below) that it found two devices, the Xilinx Spartan II FPGA (xc2s50) and a flash memory (xcf01s). (If you got an error it's probably because you forgot to plug in the power supply on the Pegasus board. If the power is on, try this again by right clicking in the main window and selecting Initialize Chain. If it's still not working ask for help.)

8. In the Assign New Configuration File window, browse to find your bit file and then click open. (Ignore the warning about the Startup clock.)

9. You will then be asked to select a configuration file for the second device (the flash memory) as shown below. Select Bypass since we are not using the flash memory to configure the FPGA.

10. Right click on the first device (the FPGA) and it will turn green. Select Program from the menu as shown below.

11. The window (shown below) with configuration options will appear. Leave all options as they are and click on OK to begin the download.

12. If all went well you should have the screen below and the green LED (LD9) on the Pegasus board near the PROG pushbutton should have turned on. If so, congratulations: you have successfully configured the FPGA.

If instead you have a red box indicating that the programming failed, check that you have the correct files for the two devices, press the PROG pushbutton on the Pegasus board and try again. If this fails, disconnect and then reconnect the 5V power supply and try again. If it still does not work, ask for help.

13. Do not save the configuration file when you exit Impact.

14. Important Please remember to unplug the power connector of Pegasus board when you are done.

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