Cu V2 video solutions

General
1

I’m looking for options to output video from my Cu V2 (+/- my IO board). Are there any shields or boards that allow a connection to a monitor?

I recently read about some folks that had homebrewed an HDMI connection for an Alchitry FPGA board. (Maybe I have it wrong?)

Any info appreciated. Best wishes,

  • DaveFer
2

Hello,

Yes, there is the Hd board for this, it offers 2 micro-HDMI ports that you can set as input or output (out of the box, port 1 is output and port 2 is input)

3

Hi gc. Thanks for your quick response.

However, looking at the sales page for that board I noted the text, “The Cu does not have the capabilities needed to drive the HDMI ports!”

I’m not 100% sure how to interpret that, but it sure sounds like it won’t work with my Cu V2.

Am I mis-interpreting that line? Thank you!

  • DaveFer
4

Oh I didn’t saw this last time I checked, but I found the reason :

HDMI need at least LVDS or TMDS voltages levels that the iCE40 does not offer.
Since the Hd board does not have such transceivers, it have to be built-in the FPGA.

So you’re right, the Hd will not work with the Cu.
You need a board with active conversion such as this, or at least some level shifting trick like this (the trick used by this one is known as AC coupling).

You can search for HDMI boards made for board based on iCE40.

5

We don’t have any convenient way to send out video on the Cu unless you’re using some LCD that accepts 3.3V parallel data. I don’t think the Cu can switch IO fast enough to drive HDMI without some parallel style adapter.

You could probably hack a VGA connector together and buy a VGA to HDMI or whatever you want. That would be the simplest approach (aside from buying an Au/Pt and Hd).

6

Hello, I have some good news about this!

I found out that using the DDR capability on the Cu works perfectly fine to run 640x480 60 fps with the Hd :slight_smile:

After doing some tests myself I found readily available examples that just need minor adjustments to run on the Cu+Hd from this github : https://github.com/merlinmarrs/iCE40HX-verilog-video-patterns/tree/main/verilog

So the Hd definitely is usable with Cu :+1:
At lower resolution than Au and Pt of course (I could run 1080p30 using my Pt, 1080p60 works too but with occasionnal loss of sync), but still perfectly usable.