Gameduino 3X HDMI

In the beginning was Gameduino, an FPGA running a tiles-and-sprites graphics core with VGA and analog audio output.

Over the past few months I have been working on a new Gameduino family member with HDMI output, combing the graphics power of the EVE with a good sized FPGA. Together the two pieces can do some quite powerful things. Here's the electrical prototype board:

The board itself is a 4-layer proto from JLCPCB. The FPGA is a Spartan 6 LX9, the BT815 is upper right, rotated 45 degrees. There's a Xilinx JTAG interface for loading the FPGA, and a SPIDriver running SPI port. This is a really nice setup for hardware bringup. With no microcontrollers involved, changing the software side takes a second, sometimes less.

A screenshot from an asteroids demo that I have been working on. It's quite impressive at 720p.

For comparison, here's a screenshot from the Gameduino 1's asteroids demo:


The GD3X HDMI will come in two versions. The first is a stand-alone module which lets you add HDMI to any design. Some specs:

• On-board: 72 MHz BT815 EVE GPU, Spartan 6 LX9 FPGA, and 2 x 1Mbyte QSPI flash
• standard-size HDMI connector, carrying 720p video and stereo 48 KHz audio
• SPI and QSPI interface at up to 36 MHz
• Multi-voice synthesizer. Instrument samples in flash
• about 30 IOs, approx 40x40mm module with castellated pads
• OSHW

The FPGA is mostly uncommitted. The HDMI encoder and synthesizer take less than 25% of the available resources, so there's plenty of room for other things. I plan to integrate the TermDriver core into it, so it will run as an ANSI-compatible text terminal right out of the box.

The second version is an Arduino shield, which has the above plus:

• a level shifter for 5V
• microSD slot
• connectors for Wii joypads
• analog audio jack (maybe)

Splitting it like this into two components means that we can make other variants for other platforms. For example Adafruit Feather and Teensy can both have plug and play adapter boards.

If you have read this far, and have a burning question like "will it do X?" or "has James remembered Y?" then please hit reply and let me know. This kind of feedback is really valuable right now!

Thanks for reading.