Logic design resources

The FPGA part of the course follows the Gateway Lab exercises developed at Univ. of Edinburgh by Khaled Benkrid and Tom Clayton.

We use the BASYS2 FPGA board shown below from Digilent for these exercises; there are many PMOD add-on boards to extend the BASYS2 functionality.

We'll be using Verilog to configure our FPGAs.

Latest news 7.4.2011: We have a working license server for the full Xilinx ISE Design Suite. Check your email to see how to use this license server.

You will need to download the following:

1. Xilinx ISE FPGA development tools. We will provide the huge installer forXilinx ISE WebPACK FPGA development tools in the class or from this torrent because the 5GB download is huge. We useutorrent for windows torrent downloads.
2. Digilent's Adept software for windows or linux, which downloads the FPGA configuration over USB to the BASYS2 board.
   You may later want to see also Digilent Plugin for Xilinx Tools which enables programming the BASYS2 directly from Xilinx ISE Impact and this informative forum post.

1. You might want to first install Digilent's Adept software for windows or linux because this goes quickly. Under Windows, the Adept installation may also need to download Microsoft run-time libraries.
2. For the Xilinx ISE installation, you will need about 15GB of free space (on top of the installer download).
3. Install either “ISE WebPACK” or “ISE Design Suite: System Edition”. If you will register with Xilinx and obtain your own free WebPACK license, install WebPACK. If you want to use the class license, then you can install ISE Design Suite: System Edition which has more powerful functionality and allows larger devices to be programmed. (It's not clear if we would ever use this additional functionality in the class.)
4. Choose to “Acquire or manage a license key” (default)
5. Install the “Cable drivers” but not “WinPCAP for Ethernet hardware co-simulation” (we will be downloading FPGA configuration over USB using Digilent's ADEPT program; at the moment it is not clear if we need the Xilinx cable drivers….)
6. The installation could take 60 minutes and expand to an astounding additional 12GB of disk space .
7. If you installed WebPACK, choose “Get free ISE WebPACK license” for the license option. If you installed System Edition, then follow instructions sent by email for using our floating license server.
8. Register with Xilinx to get your free license file “Xilinx.lic”. Save it and use “Copy license” in the Xilinx license manager to use the the license.

Simon Corrodi reports:

I installed:

1. Adept runtime
2. Adept Utilities from http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,66,828&Prod=ADEPT2
3. Xilinx ISE

The ISE Project Navigator is hidden at “ISE/bin/lin/ise”

Because the Floorplaner didn't start, I had to add to the “settings.sh” at toplevel if ISE directory:

DISPLAY=:0
export DISPLAY

Found at and some more possible problems: https://help.ubuntu.com/community/XilinxISE

Adept starts with the command: djtgcfg

djtgcfg prog -d Basys2 -i 1 -f "FILE"

(-i 1 to select the PROM)

• See the class schedule for the logic design exercises.
• The exercises are on separate Gateway labs pages.
• Adept application user manual (from Adept installation folder).
• Xilinx Spartan 3 datasheet.
• BASYS2 user manual. Very useful guide to get started with the board.
• BASYS2 schematics.
• BASYS2 UCF file. This User Constraints File is useful because you can chop out parts of it to wire up your logic to the BASYS2 board outputs in Xilinx ISE.
• The Xilinx forums have lots of activity.

• How can I program the BASYS2 using the PC connection, rather than loading it onto the PROM?
  You need to generate a programming file with a slightly different startup clock option. See http://www.digilentinc.com/Support/FAQs.cfm under the item “When I am using Export to program an FPGA I receive the error “startup clock for this file is CCLK instead of JTAG-CLK, problems will likely occur.” What do I do?” Then use the top option in Adept to load the resulting bit file directly into the FPGA. It only requires a couple of seconds to load the bit file this way, compared to 30s to reprogram the PROM.
• Which on-board clock should I use?
  You can use B8 which is the 50MHz clock source.