Atlys and HDMI on Linux

Xilinx App Note 495 describes sample implementations of DVI/HDMI receiver and transmitter on the Digilent Atlys board. I built the code using WebPACK 12.4, and it works as advertised: The colorbar test pattern displays nicely on my HDMI monitor.

Also installed Digilent's Linux version of their Adept tools for FPGA programming. They don't seem to have the full GUI version available, but the command-line tool was able to load my test code (as a WebPACK-generated .bit file) into the Atlys FPGA with no problem. Don't see any way to load code into the SPI flash: it appears that Windows-based tools are still needed for that.

Only one minor glitch: I use Debian, which isn't one of Digilent's supported distributions. In recent versions of Debian, the udev package doesn't allow plugin devices to have protection mode 0666, which means that the Digilent tools will only work if run as root.
The fix is to edit "/etc/udev/rules.d/52-digilent-usb.rules" and add a group:
SYSFS{idVendor}=="1443", MODE="666" GROUP="plugdev"
then any user in the "plugdev" group can run the Digilent tools. The /etc/group file should have a line like
plugdev:x:46:jr
where "jr" is my username.

Digilent Atlys

For Christmas, Santa Claus brought a Digilent Atlys development board for the Xilinx Spartan-6 FPGA's. Nice board, with a bunch of peripherals (Ethernet, USB, audio, HDMI!, etc).
The HDMI interface and protocol is implemented as firmware in the FPGA. My only test so far was to connect an HDMI output to a monitor and power up the board. It generates a test pattern of colored squares right out of the box. Nice. 2011 is going to be interesting.
While setting it up, I also noticed that Digilent now provides tools for Linux programming and communication with their FPGA boards. Need to check those out as well.

MHZ100Q - on sourceforge

I can now digitize one signal at 100MHz using my A/D card, capture in the Digilent Xilinx FPGA board, and upload to a PC via the USB port. I'm using Octave to upload and display the data, making a sort of oscilloscope. So I decided it's time to create a sourceforge open-source project.
It's http://mhz100q.sourceforge.net . Code is all in Subversion. It's all there, but I still need to create some build instructions and other documentation.

Cypress CY7C68013A (FX2) USB to FPGA

I just got the USB interface working under Linux for the Digilent Nexys and Nexys 2 FPGA boards. Started with some ideas from the blog at braiden.org , updated the FX2 firmware and added from VHDL test code. Details at www.sensicomm.com/main/projects/fpga/ieee_fpga.shtml#nexys_usb .