Sega Dreamcast HDMI Adapter coming soon ..

Unfortunately, a few popular consoles like the Genesis, SNES, Saturn won't be easy to mod yet, as they all output only analog video directly from their chipsets.

Those are some of the machines that would require a video core to be running on the FPGA in order to extract true digital video.
That would also mean hooking up tons more wires to the console's internal bus (or an "interposer" board used, like kevtris is doing for the Hi Def NES.)

The only other way of doing it would be to sample the analog RGB signals, but then reconstructing the colour palette in order to get rid of most of the analog noise. That would be almost like using an off-the-shelf RGB-to-HDMI box though, but there are a lot of improvements to be made in that area.

Here's a list of some of the consoles which would require a video core.
Some of them don't have a complete FPGA version yet, or may not be 100% timing accurate.
A few of them have an open-source core available, but it would still take a fair bit of work to adapt the video cores to work with a real console...

Master System < Have a TMS9918 core
Mega Drive < Have a core
SNES < Core untested
ZX Speccy < Have a ULA core
BBC Micro < Have a core
Amstrad CPC < Core untested
C64 < Have a core
Sega Saturn < No core yet? Need to check.
Sega SC1000 TMS9929


It should be possible to mod the following machines with the HDMI board (true digital video)...

Intellivision, Game Gear, Atari ST, Game Boy / GBC / GBA / GBP, TurboGrafx 16 / PC Engine, Philips CDi, Atari 2600, Atari Lynx,

Most of the following have fairly generic parallel digital RGB, so are generally more straightforward to target...
NeoGeo MVS / AES / CD, Atari Jaguar, Amiga 500 / 1200 / CD32 etc., Pana 3DO, Sharp X68000 (CZ-600CE etc.)

All the newer consoles run on 3V3, and could be connected directly to the HDMI board...
N64, Gamecube, Dreamcast, Wii (any point?), PS1, PS2, Xbox etc.

OzOnE.

 

So would i be better off just using a SCART to HDMI converter/scaler?

 

Well yes, for the time being on those specific consoles it won't be easy to extract true digital pixel-perfect noiseless video just yet, so might as well use a converter box for now. I really need to get a move on with my scaler project too.

EDIT: btw, if anyone knows of any weird versions or clones of those consoles which may actually have digital video available inside, PLEASE let me know.

Personally I think a lot of retro gaming will move over to full FPGA cores eventually, as they are generally way more accurate than most emulators but can also enable you to hook up most of the original controllers / carts / peripherals.

(Original hardware will still have many years of use yet though, and I know many people will be wanting to keep them going as long as humanly possible.)

OzOnE.

 

"drooling mod" i really cant wait to make my dreamcast hdmi lmao.

 

Don't have time to read the whole thread, but read through like 4 pages.

This is a pretty exciting mod. Biggest reason I would want it is the fact that some of the original cables to get the best picture are getting pretty expensive, some more than the estimated price of this board. Second, I know my two tvs have limited inputs, and I am tired of having to swap out cables to play on different systems. With my gc, Xbox, Dreamcast having HDMI outputs, I can just use my satalite boxes or Wii u's HDMI cable instead of pulling out my TV stand and swapping out the component input to a different proprietary cable.

 

Yep, it's about the convenience of getting the best image (and audio) on modern TVs too really.

As you know, the official Gamecube component cables are still famously expensive, and this essentially gets you a pixel-perfect digital version of that.

Even a cheap HDMI switch should work fine if you have multiple consoles hooked up and have run out of HDMI inputs on the TV.
That's what I'm planning to do eventually - I'm aiming to get as many of my machines modded with HDMI as possible.

Work is still in ongoing with the project.
We're STILL waiting for the actual date for the house move though, so I unfortunately can't do a great deal on testing new machines until we've moved in (hopefully within the next 10-14 days).


btw, I had I thought the other day - I know I can mod the Game Gear, Atari Lynx, GBA (probably DS too), Classic GB / GBC etc. but I realized that modding the Sega NOMAD should be possible too.

I'd forgotten that the NOMAD drives it's LCD panel directly too, which means it has digital signals coming from the main ASIC chip (similar to the Game Gear). That also means the chip in the NOMAD is probably the only (official) way to get true digital HDMI from Genesis / MD games apart from running the whole Genesis core on an FPGA.

(The standard Genesis / MD consoles only output analog RGB video from the chipset.)

Anywho, I might get time in the next few days to get the Game Boy Player working via HDMI.
I have it hooked up to a board already, but need to do a bit of work on the code to get a proper display on the TV.

I still have my soldering station, TV, and PC here, but literally everything else in the whole house has either been packed already, or is sat in a shipping / storage container. lol

No way my PCs are going into storage though.
I do make regular backups made, but pretty much every single project I've done is still on this HDD.

Oh yeah - also keep forgetting that the HDMI boards will be stackable (or simply joined via a cable), so we might be able to do things like using multiple boards for playing four-player Goldeneye on separate TVs.

The boards will also be able to simultaneously drive an LCD panel directly, and make toast.
(the very last part might not be true. )

OzOnE.

 

So since the Nomad has digital signals, it can be HDMI modded? Holy crap that's awesome! Now all we need is a way to hook up the Sega CD/Mega CD to it and presto! We have the ultimate Genesis/MD system. Would it even be possible to connect the Sega CD or do we have to recreate the circuitry that interfaces the Sega CD with the MD? Any ideas on how one could do that and what parts would be needed?

 

Could it be possible to cut the split screen into sources ??? Ergo no screen hacking?

 

Yep - I'm fairly certain the Nomad is using similar signals to the Game Gear at least, so it should be possible.

Not sure if the Nomad ASIC chip has all the required signals for hooking up a Sega CD, but it's possible.
Most of the signals will be available on the cart slot though, since the expansion port on a normal Genesis just exposes the main CPU address / data bus (plus a few more control signals).

I don't think the Nomad schematics are public though, and I don't own one, so I'll have to try to get hold of one at some point (or borrow one).

Not sure what you mean by screen hacking?

btw, another possibility will be to output side-by-side format from 3D games to a modern 3DTV.
That would depend on the chosen console and on how the game normally outputs 3D (eg. shutter glasses or anaglyph etc.)

The Master System uses shutter glasses, but it's also one of those consoles which only outputs analog RGB from it's VDP chip.
Just a thought. lol

OzOnE

 

Hmm, it seems I could be wrong about the Nomad...

Apparently, the ASIC is the same pinout as in the Genesis 2 VA3, so it might not use digital video for the LCD after all.

http://console5.com/wiki/315-5660

There are quite a few pins on the stock Nomad LCD though.
Could just be analog I guess. LCD panels with analog RGB input certainly do exist, and were used a lot on 80s / 90s stuff.

OzOnE

 

Screen hacking also known as Player 2 looking at players 1 side of the screen to figure out where he/she is.

 

That's not screen hacking, that's screen looking. Hacking is when you inject new code into something or are trying to break into software that you do not normally have access to, which is illegal in most cases. Screen looking is just old fashioned cheating. I used to do it a lot when playing games with my sister and is the main reason why my parents got me my own Xbox 360. I have since learned to stop in case you were wondering.

 

I actually remember now that it is actually a term used for looking at another player's screen / part of screen.
It's just that I hadn't heard it used in a long time...

http://www.urbandictionary.com/define.php?term=Screen+Hacking

But yes - that's the idea - you will set a jumper / switch on each HDMI board so it will zoom in to only one quarter / half of the screen, or simply blank the upper or lower half for 2-player.

So, in games like Mario Kart 64 in 4-player, you will only ever see your own screen / kart on your TV.

The FPGA only has around 52KB of on-chip RAM though, so it won't be enough to hold a full video frame at the full colour depth.
But, you can code it so only the chosen pixels / lines get stored, and hence do zooms and other tricks.

(I could also feasibly split a video frame over multiple boards.)

The main downside to using a frame buffer is that it will add an extra frame of latency in most cases.

I'm intending to add an external RAM chip to a future version of the HDMI board which will allow us to do other tricks / effects.
If you think about it logically though, most framebuffer tricks will add at least one frame of extra lag because you have to buffer an entire frame before outputting it to the TV while the next input frame is being written.

There are certain tricks you could do that minimizes lag / latency though, like generating the Sync pulses in a different place to normal so you can move the whole image around on the screen etc.

For example - By delaying the Vsync pulse, you could move the lower half of the image "up" the screen, then do a vertical stretch to the image with a smaller amount of framebuffer RAM.

I'm not sure how good multiplayer N64 games will look when zoomed in, but probably way better than doing it via analog at least.

OzOnE

 

Which one? The only one I know about (Peter Wendrich's, aka Syntiac) comes with a "look, but don't touch" license.

 

Ahh - well that will have to be figured out with Peter then, I guess.

https://github.com/wsoltys/pacedev/tree/master/sw/src/platform/c64

That's another reason I will be concentrating on the easily moddable consoles first (with a digital video bus) - I haven't yet looked at all the different licenses, nor asked the authors yet about what can and can't be used from their projects.

The MiST is using Peter's core as well by the looks of it though, and supposedly under the GNU GPL v2 license?...

https://code.google.com/p/mist-board/source/browse/#svn/trunk/cores/c64

ie. "Have core" on my list of machines merely means that an open-source core exists, so it may be possible to get true HDMI working on that machine - it was a just a quick preliminary list.

OzOnE

 

Any new news on your hdmi project???

 

Check out his official thread (post #130). He said he is busy with his house so he probably won't be on for a few weeks. I talked to him in the shoutbox and his scaler is supposed to be supporting all kinds of inputs like RGsB (sync on green) and 15KHz VGA (RGBHV). I also asked if he would add Sync on Red (RsGB?) and Sync on Blue (RGBs?) support but there is no point as very, VERY, few devices use those RGB sync signals.

 

Thanks for the update. Hope to see this out before psio. Plan to have it installed on my dc and psx

 

it's been a while now, is the project down somehow ?

 

Hi,

I've literally only just got the boards and my soldering / test stuff back out of storage after moving house etc.

I currently have the HDMI proto back on the bench though, and I'm doing more testing atm.

I can't promise that I'll be able to get anything released soon, and it will be at least 5-6 more weeks before I'll have anywhere near enough money saved to do a larger order of 20 or so boards.

This is current state of my new "workshop" room, and you can just see the small HDMI board in front of the mouse...

https://i.imgsafe.org/6bc4909.jpg

And here are about half of the boxes I'm going through atm. lol

https://i.imgsafe.org/755b71a.jpg

I really wish I had better news atm, but it's been a terrible 3-4 months tbh.

I'll still be trying my hardest to get this project released though, even if it's just for the Dreamcast initially.

The Game Cube will likely follow closely after that, but I don't think I'll be able to managed any "up-scaling" on the board itself now.

Again though, most TVs these days do a fine job of scaling an SD input to the native panel res anyway, it was mainly on the analog SD inputs that some TVs got a bad wrap for tbh.

So, the board may only be outputting the native res of the console (480p or 576p, or line-doubled from 240p / 288p).
The TV or monitor itself will then do the job of up-scaling, and it usually looks fantastic anyway.

I personally can't see the benefit of doing the up-scaling on the FPGA side, as it will likely introduce more latency, and can't really add any extra detail anyway (not without a framebuffer and advanced scaling techniques, which is what 99% of TVs do already.)

At the moment, there is essentially zero noticeable latency on the HDMI output itself, because modes like 480p / 576p (or line-doubled 240p / 288p) don't need a framebuffer. For 480p / 576p, the signal just gets parsed then sent out pretty much untouched via the HDMI Tx chip.

On the GC though, I may add the option for that simple LERP (Linear Interpolation) on the chroma, as it does give a subtle yet noticeable improvement.

I also want to try to avoid adding an on-screen display if I can, as that will mean either using an IR remote, or hooking the board up to one of the controller ports on each specific console. I was thinking that just a few simple switches would be OK for most people to enable / disable things like scan-lines, LERP, line-doubler etc.?

I'm actually testing the HDMI board right now with the scaler board as well.

Currently it's just driving a small LCD panel directly, but I will eventually get around to hooking up another HDMI board to that so it can output to a TV / monitor / capture card instead.

The scaler project will be for making it much easier to hook up consoles which can't easily be HDMI modded, like the Atari 2600, Intellivision, Colecovision etc. which only have RF output (technically I have looked into HDMI modding those as well, and most will be possible in future. )

(I'm no doubt repeating myself here, but just to re-iterate)...

The scaler board will allow input of HDMI, VGA, Composite, and Component, analog RF, and possibly S-Video depending on how it works out. It will come with a remote, have up-scaling to 720p or 1080p etc., and will be MUCH cheaper than the likes of the X-RGB Mini etc. Maybe not quite as cheap as those GBS-82x0 boards of course, but pretty good (and far more feature-packed).

The board also has a built-in audio amp, so it can be hooked up directly to speakers, plus it has an audio input (for VGA / PC), headphone output etc. Again, depending on which model I end up with, it may also have the ability to play back 1080p MKV movies from a USB stick.

SO much work to do now (again), but at least I don't think we'll be moving house again for many more years.

I'll try to keep this thread updated more, but I really am trying to get more consoles / handhelds tested atm, and make sure the Dreamcast code is robust etc. (and the board design itself).

OzOnE.