Home made FPGA PAL vectorscope

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markaren1
Posts: 59
Joined: Sat Sep 10, 2011 8:49 pm

Home made FPGA PAL vectorscope

Post by markaren1 » Wed Oct 15, 2014 11:50 pm

Hi All,

I have been tinkering with some real-time video processing using a DE0-nano FPGA board and a couple of home-made PCBs.

Video codec PCB has 2 x 12 bit ADC and 2 x 14 bit DAC, both running at 25Msps. Card also has anti-alias and reconstruction filters.

User interface card has Ethernet, SD card, 2 x USB, bluetooth etc, but only one of the USB comms ports is used in this video, and connects to a soft-core processor (NIOS II) which manages UI and the digital PLL.

Project started out as an experiment to see how difficult it was to lock a locally generated carrier to colour burst from a PAL video test signal, and as usual everything has got a bit carried away.

Video input is colour bars from a Sony broadcast camera.

Output has a real time monochrome display using a pair of 256 x 256 pixel buffers swapping every frame (ping - pong). Output format video is 312 line progressive at about 50Hz driving a 7" LCD.

All memory is on board the FPGA. Current build uses 31% of available logic elements and 47% of available RAM.

And a short video is here : https://www.youtube.com/watch?v=8o0WLwx-md0

I continue to be amazed what can be done with these NZ$110 FPGA development boards.

From New Zealand in spring time.

-mark

G4GUO
Posts: 729
Joined: Tue Feb 16, 2010 12:51 pm

Re: Home made FPGA PAL vectorscope

Post by G4GUO » Thu Oct 16, 2014 6:41 am

Nice project Mark, yet again it shows us all what an important technology FPGAs are
for the hobbyist. I noticed from my Twitter account that FPGAs are starting to be
promoted to the 'maker' community too with FPGA shields for the likes of Beagle Bone Black.

Things like Altera SOC and Xilinx Zynq look appealing but at the moment the ARM cores on
those devices are pretty slow. The Parallella boards look interesting too and there is an
RF "shield" in the works for that. Just needs some video capture 'shields' now.

- Charles

markaren1
Posts: 59
Joined: Sat Sep 10, 2011 8:49 pm

Re: Home made FPGA PAL vectorscope

Post by markaren1 » Fri Oct 31, 2014 8:47 pm

https://www.youtube.com/channel/UC3mio9 ... N0rGuWEFQw

now with graticule, status display, and internal colour bar gen (with bouncy ball)

-mark

2E0DTX
Posts: 45
Joined: Thu Oct 03, 2013 6:32 pm

Re: Home made FPGA PAL vectorscope

Post by 2E0DTX » Sat Nov 01, 2014 8:36 am

Come on!! Now that's just showing off :) :)

Seriously though what a nice, in every sense, project. Well impressed.

Any thoughts of making it on a PCB as a kit or has the challenge essentially been met?

73's

Laurence 2E0DTX

markaren1
Posts: 59
Joined: Sat Sep 10, 2011 8:49 pm

Re: Home made FPGA PAL vectorscope

Post by markaren1 » Mon Nov 03, 2014 5:20 pm

Hi Laurence,

Thank you, high praise indeed.

It has served well as an educational platform, which was the original intent - verilog programming as well as SMD assembly.

The finest pitch feature on the PCB are the ADC pins (250 x 750 microns), and was quite an interesting time just getting the ADC loaded.

The Verilog caused several more clumps of hair to be pulled out, so am quite bald now.

So, the project is pretty much complete now. I had planned to improve signal status (no video, chroma out of lock etc.) but that is all obvious from the state of the display.

Quite surprised how useful a 288 line progressive display is, 256x256 monochrome graphics may not be that sexy, but there is room for a quite a few instances within the FPGA.

Just added wireless control using a smart phone over bluetooth. Not sure that there is enough bandwidth back to the phone for a real-time display.

Getting more PCBs loaded would be horribly expensive, so no plans for kits.

http://www.idesignz.org/AudioBox/AudioBox.htm is in a similar vein, but audio related.

Need to add a new acronym - Older, Wiser(?), Balder -- OWB

-mark

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