VGA output via fpga

Includes but not limited to: SNES, Genesis, Sega CD, PlayStation 1, Nintendo 64, Dreamcast, Game Gear and I guess the Virtual Boy.

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Re: VGA output via fpga

Post by User » Mon Mar 18, 2013 8:04 am

I hope for some new infos from MGC in 5 days!

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marshallh
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Re: VGA output via fpga

Post by marshallh » Sat Mar 30, 2013 5:02 pm

Well it didn't make it to MGC.. I worked hardcore on it the preceding 2 days and found out my DDR bga setup was working great, and that part was OK, save for a few edge case bugs in my controller.
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Re: VGA output via fpga

Post by User » Sun Mar 31, 2013 6:34 am

So you found the problem that was causing the power transients?

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Re: VGA output via fpga

Post by OzOnE » Thu May 09, 2013 1:59 pm

Hey, Marshall,

It's been a long while since we last spoke, but I found some spare time to play with some retro goodness.

I registered at GC Forever yesterday to mention a possible HDMI mod for the Gamecube.
I didn't check your progress on here first, and so glad to see the N64 board has DVI too now. :D

So many questions...

Are you interested / do you have time to do a GC version?
I'm currently working on a bit of code to do the video decoding. I'll be hooking up the GC later tonight.

Have you done any testing for the GC digital AV output / spun any boards yet?

I've been trying a direct HDMI output from the Altera, but your solution is a much better idea tbh.
The voltage levels from the LVDS outputs isn't exactly going to be easily standardized using the direct method, so a proper TX chip is the way to go.

I'm just crap at doing the board design - How the hell did you get so good at it?
I'm assuming you're using something like Altium Designer now?

Regards,
OzOnE.
EDIT: Oh, and I finally got around to buying a DE1 board. Having fun playing with minimig and HDMI output.
Still using the cheapo Chinese dev board for most evil experiments though.

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Re: VGA output via fpga

Post by marshallh » Tue May 28, 2013 4:23 pm

Ozone,
Wow, it's been a while.
I have been asked a couple times through email if this could be adapted for use with Gamecube. If it uses digital video output, probably yes. IIRC there needed to be some color space conversion as well.
There's a gamecube somewhere around here, havent booted one in a few years (never owned one)

I am working on the next pcb layout right now so if there needs to be more input channels this would be the best time to know.

The actual problem with the PCB I finally determined was some excessive capacitive loading on the VGA hsync line. At this point I think it was a fab error, probably an internal partial short. After swapping IOs around the vga test pattern was working.
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Re: VGA output via fpga

Post by User » Tue May 28, 2013 4:44 pm

Great to hear this project is still alive, i´m checking this thread almost on a daily basis.

Gamecube support is something i would be very interested in too.

Do you plan to still use a DVI port with the newest rev of the board or go with HDMI?
It would be awesome to have digital sound over HDMI (if this was possible).

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Re: VGA output via fpga

Post by Ashen » Wed May 29, 2013 8:11 am

Marshall, here is the GC's onboard video encoder pinned out:

(cred to Megalomaniac from GC-Forever for taking the time to mostly pin things out)
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All the signals in the left side of the pic/pinout are the inputs and come straight from the GPU on the GC. These datalines also pass straight to the digital AV out port on the GC and feed the MX chip that built into the component cable, which then spits out component/VGA.

Hope this helps a bit with figuring out if you need any extra inputs. Would be amazing if this project could be easily adaptable to the GC also. I'm looking forward to it either way of course. :D
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Re: VGA output via fpga

Post by marshallh » Wed May 29, 2013 8:56 pm

OK I have added the extra two signals to the connector on the next pcb as well as a jumper for selecting GC mode (note this only provides the possibilty, the actual functionality doesn't exist)
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Re: VGA output via fpga

Post by OzOnE » Thu May 30, 2013 12:23 pm

Hi, Marshall,

I'm still not sure if direct HDMI output is the way to go?
I think it will be difficult to get the voltage swing right so it will work with all TV's / monitors.
(The HDMI output works fine with my Samsung LCD TV, but not with my monitor.)

The GC HDMI project is on hold atm, I'm just so busy with tons of other things.

If you can find an IC which outputs both HDMI and VGA, that would be ideal.

I also thought about using one of these cables...
http://www.ebay.co.uk/itm/HDMI-HDTV-to- ... 27d200d061" onclick="window.open(this.href);return false;

I bought one recently and mapped the pinout (can't find the txt file atm).

That might cut down on the number of connectors and make the PCB more streamlined?
Although I think some of the VGA pins are shared with an HDMI channel, so might complicate things?

I'm still having trouble with the scandoubler on the GC, and haven't yet got around to getting a DVD-R working on the US GC to test 480p.
(I have the two Xeno chips now, so just need to solder it to the US one and buy some more blank disks).

In theory, 480p signals should pass straight through to HDMI.
(Even though the HDMI standard supports interlaced as well, the protocol is more complex for the lower resolutions 'cos you need to do pixel / clock doubling etc.)

I'll send you the current code, as I'm sure you'll be able to knock together a MUCH better / simpler scandoubler (I'm attempting to use the "TV" example from the DE2 disk).

YCrCb to RGB Colour space conversion appears to be working fine though. 8)

If you could add GC and HDMI support to your board, I'd love to buy a few of them.

EDIT: Oh, and looking at Ashen's / mega's pinout has reminded me - it would be great if your DAC chip could do Sync-on-Green for Component output too?
I'm guessing most of the Analog chips nowadays can do this anyway?

I don't think anyone would mind if we left out Composite too? Although this is benheck after all, I think portable modders would appreciate as many types of output as possible. :P

Regards,
OzOnE.

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Re: VGA output via fpga

Post by ToñoGK » Thu Jul 04, 2013 12:56 pm

Can't wait!

Any update, Marshall?

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Re: VGA output via fpga

Post by Tighe » Tue Jul 09, 2013 9:23 am

Bumping this thread!

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Re: VGA output via fpga

Post by marshallh » Wed Jul 10, 2013 6:56 pm

Things are coming along on the next pcb
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Re: VGA output via fpga

Post by marshallh » Sat Jul 13, 2013 6:41 pm

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Re: VGA output via fpga

Post by User » Sun Jul 14, 2013 9:09 am

Since you added the possibility for GC compatibility with the last board, would this also support Wii?

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Re: VGA output via fpga

Post by Diminuendo » Mon Jul 15, 2013 10:55 am

User wrote:Since you added the possibility for GC compatibility with the last board, would this also support Wii?
There already ways to get HDMI and VGA from a Wii. The GameCube has a special cable that is now more of a collectors item because of the limited quantity out there. It is hard to get a high quality video signal from both the GameCube and N64. it would be a waste of time (in terms of market) to add Wii support.

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