Sega Dreamcast HDMI Adapter coming soon ..

I know Id love one on the original Xbox, might be more complicated due to the HD resolutions it supports though?

 

The original Xbox is about the same soldering task as the Dreamcast, so it's one of the trickier ones, but is definitely doable.

It will also be possible for it to output native 720p or 1080i via the HDMI board.

That part should work fine, it's just up-scaling that I might not have chance to finish and test before releasing the first version.

I do intend on testing the board with the Xbox soon. I just have to find the box with my Xbox in first. lol

I've been doing some more testing today and the board is outputting 720p and 1080i (from a test pattern) just fine.

I still have one of the original proto boards hooked up to the Dreamcast, and that is rock-solid as well (native 480p output).

After the Dreamcast, I want to do more testing with the Game Gear, and also fix the last little issue with the Atari Lynx...

ie. filling in the "missing" lines, and fixing the line alignment...

https://i.imgsafe.org/28b252f.jpg

Although, the lines do give it a kind of "retro" look. hehe

The Atari Lynx could do with vertical scan-lines on the HDMI image though, just for old time's sake.

OzOnE.

 

thanks for the big share... I am really looking forward to this...

 

great news ! thanks for updating us ! if u need some money to pay first bach why don t u set up a paypal donation button ?

 

Any news on this, are we likely to be able to buy any of these in the near/distant future?

Ted.

 

I know I've said this too many times in the past, but we're STILL working on it. lol

Sorry it's taking so long, but it's easy to underestimate just how many pitfalls and hurdles there are with this stuff.

This is the first time I've really tried to turn a project into an actual product / kit, so tons of stuff to check etc.

Slowly getting there though - I just today installed an older prototype into a DC which will be sent off to StoneAgeGamer so it can be shown at the TooManyGames expo in Pennsylvania.

Just today uploaded a quick vid of the older prototype running (mainly to show Ryan at SaG)...



I also have the final-final prototype board on the desk right now that Mr [RDC] just shipped to me from the US (to UK).

We had some issues with it, but only because we happened to pick one of the boards that OSH Park managed to screw up (had a small short on one of the power rails). That's kind of half expected with a prototype service though, and just one of those things.

So I now just have to order a few more chips later today, then confirm that the final-final board is working 100%, then we can finalize the custom flex cable design, save some pennies for the first large batch of boards / cables, then it's all systems go.

Oh, and in the mean time (while waiting for prototypes and parts), both Mr [RDC] and I have been working on another awesome project which will run alongside the HDMI stuff.

It just so happened that [RDC] had already started work on the exact same thing when I mentioned it to him. Weird. lol

If you've seen some of my older threads about the NAOMI / AW stuff, you'll know that I was working on reversing the pinouts for the HOLLY chip so we could be 100% sure about the pin numbers in the old VA0 schematics.

Well, we've sort of taken that to the next level...





OzOnE.

 

I'm now also migrating over to Altium Designer instead of Eagle.

It's actually not too bad at all to get started with, and I'd been putting it off for far too long.

As you can see from the last post, it can also view the board in shiny 3D.

Essentially we're looking to make a new motherboard for the DC.

The very first ones will just be a "stock" version to make sure everything works 100%, and then we'll be adding the footprints for extra RAM to take the "core" up to the NAOMI 1 standard.

Eventually, that could allow us to use an add-on board for emulating NAOMI "GDs" / carts too.

We obviously want to add breakout headers for the full G1, G2, Maple bus, extra chip selects, and digital video / audio signals too, so the core board will completely max out the core part of the DC, and allow all sorts of upgrades to be added.

Naturally it will have HDMI output too, and I've just finished testing a new chip which does the simultaneous up-scaled HDMI and VGA / Component output.

(for the HDMI board, we're sticking with the original chip because the new one does get rather hot, which isn't ideal for handhelds etc.)

Anyway, that's where we are atm, but my main focus is still on getting the HDMI kits released.

OzOnE.

 

Wait a minute, you're designing a complete refactoring of the dc motherboard?
How would you get a sh4?
...?
What?

Would be awesome to integrate a minimal size version of that with gdemu in a tiny case...

...

 

Yep - we're looking to get all-new PCBs made for the DC motherboard.

I know I kept saying for years that I was going to finish that N64 mobo too, but we've actually got further with the DC now. lol

It's mainly down to Mr [RDC]'s sheer tenacity / skill and our combined OCD tbh.

I've wanted to do the full redrawn DC schematics ever since "l_oliviera" uploaded the VA0 schematics all those years ago.
It's awesome that he did upload them obviously, but it's just REALLY hard to tell some of the pin numbers apart.

I started testing the pads on that NAOMI I bought many years ago (which had already had it's Holly chip removed), I'd confirmed / reversed most of the pinouts for it. We already knew the SH4 pinout, since you can just download the datasheet for that.

So, after realising that [RDC] had also done some work on this, we joined forces about two weeks ago.
After only a few days, he had already redrawn the FULL schematics for the VA0, VA1, VA2.1, including all the passives. lol


For the new board, we'd have to pinch at least the Holly chip from original DCs (unless anyone knows where we can buy them?)

You can still buy the SH4 on AliExpress, but we'd need to re-ball the Holly chips of course.

http://www.aliexpress.com/item/5pcs..._1&btsid=15256745-56d5-4a05-8cf9-8c963b732daf


And, since we'd be pinching the Holly chip from the DC, we might as well the SH4 as well, and get them both re-balled.

I was looking into using more modern BGA RAM chips though, as we'd obviously need more RAM for the full "NAOMI" style amount.

The RAM stuff got more complex when I looked at the NAOMI board again the other day though - the NAOMI uses four 16-bit wide chips for the SH4 instead of the two 32-bit wide chips on the DC (as the NAOMI spreads the 64-bit bus across all four chips).

The AICA on the NAOMI uses one big 64 Mbit RAM chip, so it has 54 pins instead of 50 on the DC.

So, the only RAM that's directly interchangeable between the DC and NAOMI are the Holly RAMs. lol

It looks like you can still buy the "standard" TSOP type RAM chips anyway, so we'll probably stick with those as it does make routing the board easier too (and might allow us to re-use the old RAM from the DC for "half" the RAM).


I'm usually against pinching parts from stock hardware, but I think it's fair enough if we'd be re-using them to fit back into the original DC shell anyway, just with many enhancements.

(fair enough, the DCs are still relatively "rare", even compared to the Speccy. There were only about 9 million DCs sold, and only 5 million Speccies. That's compared to 84 Million Xbox 360s. )


Oh, and as for the tiny Dreamcast idea...

 

There's a fair amount of dead motherboards because their flash fried or other issues that you could salvage parts from anyways, I got 2 such board myself!

Could you make the design that small by default, with ribbons/daughter pcbs to reach the DC ports if need be? Could that make it cheaper as the pcb area is smaller?

I'm actually very interested in the tinydc idea. That small pcb + gdemu + minimalist acrylic case = slick little DC.

 

Yep, we were discussing that yesterday actually.

It does seem to make sense to me to make a small-ish "core" board, and then leave off all the "analog" stuff.

That would then allow you to choose between having the analog video / audio outputs, up-scaling HDMI / VGA, "native" 480p HDMI (mildly cheaper), or a combination of those.

Although, that would still mean getting other smaller PCBs made which would likely work out as the same (or more) area than one big board tbh.

So, we're probably just looking at making a stock board initially, but with the extra footprints for the full amount of RAM (gonna have to figure out a better way of saying that. lol), and some breakout headers for all the digital signals.

I do also love the idea of a mini DC too though. hehe
That board example above is actually slightly smaller than the GD board.

Even with the older-style TSOP RAM chips, it could still probably be made to fit underneath the GD drive.

But, if we're gonna go that far, we might as well do a mod to use a a laptop style tray / slot loading CD drive too.
A "Dreamcast Super-Slim" would be a pretty neat thing to behold.

OzOnE.

 

I'm on the edge of my seat, awaiting more details of this new adventure. It would be really cool to see you guys pull this one off, AW/Naomi games on Dreamcast........ :O

 

this is insane lol

 

Sorry if this has already been answered, but will this have a pass-thru header so those of us using GDEMU or USB-GDROM will still be able to do so? Thanks, videos look amazing!

 

Yep - for the "enhanced" version of the board (or the "Dreamcast Too", as I like to call it), we'll be leaving the G1 header on there.

The good thing is, different parts could always be left off, so we could build the Super-Slim etc.

OzOnE.

 

Do you have an expected release date/month for the HDMI adapter, are we likely to see it before the year is out?

Ted.

 

I did not expect to see people discussing prototypes of a revamped dreamcast motherboard that could support components to permit the DC to play Naomi/AW games in a thread about an HDMI adapter, or a separate design resulting in the DC taking up a much smaller form factor! I think I speak for the dreamcast enthusiast community at large when I say, I am highly interested in this prototyping going on and hope something physical and tangible comes out of it, preferably for purchase by dreamcast fans everywhere

 

Working hard to get the boards / kits released within the next 3 months if at all possible (for the Dreamcast at least.)

I got the final-final prototype working just this morning though, so the design is finally locked-down.

Now it's a case of finishing the custom flex cable to match this board, then getting a few of those made for testing.
I've just ordered parts for another 5 prototypes as well.

I've also been talking to Ryan from StoneAgeGamer just now about the TooManyGames thing.
The final board is running - I now need to hook it up to the DC, probably tomorrow, then ship the whole thing off for the demo at the expo.

I did order some connectors and ribbon cable to match the final board, but I don't think they will get here in time for me to have the DC ready for the demo. So, it'll just be a case of soldering the Kynar wires to the board again for now (not too much of a problem).

We're still aiming to keep the price of the board / kit around $100 (£65) if at all possible, but it's tough to get exact quotes on the flat flex cable until the design is sent in. So, it may be slightly above that price. We'll have more details soon.

It's not likely that I'll be able to manage decent-looking up-scaling to 720p or 1080p on this board before release, but new firmware will be made available for if / when that does happen. (firmware updates may or may not require the purchase of a cheap USB Blaster clone, but we're still working on negating the need for that.)

OzOnE.

 

@dark - yeah, I REALLY need to make a new thread for the motherboard stuff. lol

Sorry, just been so busy trying to get this final board up-and-running (after the usual minor "mishaps" and "prototyping pitfalls").

We're still prioritising getting the HDMI mod boards done though, as the DC motherboard project will take a lot longer to finalise.

The toughest part of the DC mobo will be the manual routing of all of the tracks, and then the painstaking triple-checking of everything before we send off for the first prototype PCB.

Once the "core" of the board is routed though, we will literally be able to cut 'n' paste it onto different board designs (with various added features etc.)

OzOnE.

 

i dont know if you have the doc with the title "Dreamcast Hardware Specification Outline" and another one with "Dreamcast/Dev.Box System Architecture" i found it here
under E-Links > System Architecture:-1 -2
http://sabia.tic.udc.es/gc/Contenid...acionVideoJuegos/DreamCast/MENU/menu-web.html

you can see lot of details and see that the holly chip is a PowerVR2 GPU i hope this can help you