HDMI Breakout Part 2

 I see the PCB in my Nov 6, 2013 post is getting some interest, so here's more info about it. The image to the left is a Kicad screenshot. The breakout connector (P1, CONN_5X2) is at the top, and pin 1 is the top right pad. Odd-numbered pins on top, and even-numbered on the bottom.
Top connections are:
1 Ground
3 HOTP-J
5 DCC_D-J1
7 DCC_C-J1
9 CEC-J1
and the bottom connections are:
2 +5V (J1 and J2 both)
4 HOTP-J2
6 DCC_D-J2
8 DCC_C-J2
10 CEC-J2

So to use the board as a passthrough connection, add jumpers connecting 3-4, 5-6, 7-8, and 9-10. Obviously, it's NOT a good idea to have a jumper connecting 1 and 2 (ground and +5V).

Here's the schematic. Pin 20 is the metal shell of the connector, not a real pin.

HDMI breakout PCB

This is probably only useful to a small handful of people, but if you're and engineer developing HDMI products that might include you.
For some work developing HDMI-compatible FPGA code, I needed to observe the control signals with a scope. So I built up this little breakout PCB. The high-speed video TMDS signals are routed directly through from one connector to the other. I tried to keep them equal length and as short as possible. Don't have any way to verify impedance and reflections, but it works ok on one TV with short HDMI cables.
The low speed (CEC, SCL, etc) signals are brought out to the header in the back in the photo. Jumpers allow the signals to pass through, or they can be disconnected to test and modify them.
The PCB is shared on OshPark. See http://oshpark.com/profiles/sensicomm  if you want to use this design. It uses standard HDMI female connectors, available from DigiKey and many other vendors. Soldering the fine-pitch surface mount pins on the connectors is a bit of a challenge. I tried soldering individual pins, but ended up using the flood it with solder and mop up the excess with solder-wick method.

ATLYS HDMI

Followup to my previous post, related to Kaveh's comment. This post describes how I set up HDMI TX and RX.
To test HDMI TX and RX, I loaded the HDMI switch example from Xilinx App Note 495. Loaded Top-level files dvi_demo.v and dvi_demo.ucf into ISE WebPACK, along with all the lower-level modules they require. Everything is in xapp495.zip from Xilinx.
Board configuration:
JP6&JP7 in: link SCL/SDA between TX&RX.
JP11 in: boot from USB stick.
JP5 in: Enable J1 HDMI input.
Connected J2 to display, J3 to source (J1 sometimes works as well).
I load dvi_demo.bit from a USB stick - takes about 30 seconds each time.
Tested with a Samsung TV and DirecTV box and Samsung BluRay.
The LED's show that RX is sync'ing with the signal and the display shows up on the TV. Tried several channels at different resolutions (no 1080p ones available). Sometimes had to unplug and replug the HDMI cables to get things to sync up. Just video, no audio passing through yet for some reason.
So that's my progress so far.

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.