NeoVGA: Lagless, pixel-perfect line doubler for Neo-Geo MVS and AES

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
I'm in San Diego. The project is still not dead, but I've been going really hard on this Sega Genesis project. I did get around to installing software and plodding away at the schematic a little more. Somebody has reached out to me with interest in doing the PCB manufacture part of this, so if that gets picked up that'd be great. The PCB I have in mind should be able to support at least Neo-Geo, CPS1/2, and Nintendo 64.
 

Lemony Vengeance

Mitt Romney's Hairdresser,
Joined
Jan 30, 2012
Posts
4,204
I'm in San Diego. The project is still not dead, but I've been going really hard on this Sega Genesis project. I did get around to installing software and plodding away at the schematic a little more. Somebody has reached out to me with interest in doing the PCB manufacture part of this, so if that gets picked up that'd be great. The PCB I have in mind should be able to support at least Neo-Geo, CPS1/2, and Nintendo 64.

Thx for the update and hard work! Is love to help test in any way that I can.
 

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
Thx for the update and hard work! Is love to help test in any way that I can.

I'm thinking of putting together a half-ass solution for the mean-time so it's better than nothing. My current dev setup is a Digilent CMOD S6, which is a Xilinx 6 board in a 64-pin DIP package. It has an EEPROM on board and enough IO for the project (just barely). I'm thinking of making a PCB for one of those to plug in to, which just breaks out the inputs for the Neo-Geo and the VGA DAC. That'd let someone throw one of these together for ~$90. Expensive, but it's an early prototype and until I have the time to put together a PCB it's better than nothing. I'll see about doing something like that next weekend...
 

DrHuxtable

n00b
Joined
Apr 3, 2015
Posts
22
Mike,

1) I need a CPS2 Component solution.
2) Any plans for NES, SNES, Genesis, PS1 in Component? If I had all that, I'd be good for life. You'd probably make a killing if you supported the console market.

Please keep us all updated and/or PM me when you're ready to take my money. Thanks.
 
Last edited:

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
The problem with consoles is that almost none of them have a digital pixel bus available. Getting clean output is possible with a really nice ADC and synchronizing the sampling to a pixel clock, but that's still remarkably more involved than a system with a pixel bus digitally available (Neo-Geo, CPS1/2, N64/GCN*, etc).

I have some ideas in the works for Genesis, though - it can be coaxed into giving digital pixel index data, much like the NES. There are some technical challenges, but that's the system I plan on targeting next.

I'm a piece of shit though; I keep sitting down to work on the PCB and I get torn away by other projects or work. As far as VHDL code goes, though, the CPS2 work is done - 240p or 480p component and RGB/VGA all work great.

As for the NES, using Etim's NESRGB project it wouldn't be hard to take the RGB signal generated (which is digital before the DAC on board) and do a digital conversion to YPbPr. A CPLD could do that work easily...
 
Last edited:

KalessinDB

Mr. Big's Thug
Joined
Dec 17, 2013
Posts
202
Tim's got a YPbPr converter to go with his NESRGB kit. I've got one in my NES and it's beautiful. I hear the same relatively cheap board can be used on other RGB systems too, which is nice considering a jrok can be expensive overkill.
 

420p

King's Dry Cleaner
Joined
May 25, 2013
Posts
383
But most modern TVs don't eat 240p/288p via component. Dunno from the top of my head, what the jrok throws out via component.
 

KalessinDB

Mr. Big's Thug
Joined
Dec 17, 2013
Posts
202
But most modern TVs don't eat 240p/288p via component. Dunno from the top of my head, what the jrok throws out via component.

I've heard this, but am skeptical. Or perhaps very lucky. Cuz I'm 5/5 on TVs at my house, my best friend's house, and my parent's house taking 240p via component just fine, and they're different brands.
 

White Devil

Hardened Shock Trooper
Joined
Nov 26, 2012
Posts
448
Couldn't this be solved with an upscaler? The SNES component seems pretty legit.
 

420p

King's Dry Cleaner
Joined
May 25, 2013
Posts
383
If I use an upscaler, then I would pump rgb into it.
 

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
But most modern TVs don't eat 240p/288p via component. Dunno from the top of my head, what the jrok throws out via component.

JROK converter will just change colorspace, but still output the resolution it's given (that's a good thing about it).

Adding a line doubler that takes the output from the NESRGB is not out of the question. Stay tuned.
 

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
Okay, I've been complete garbage, BUT I finally began actual PCB work. The schematic is not too complicated and I expect to be able to use the same PCB for CPS1/2, Williams arcade, etc as new systems are added.
 

fenikso

Slug Flyer Pilot
15 Year Member
Joined
Oct 6, 2004
Posts
3,932
Ok, CPS2 would be tits. Do you need an A board to work with?
 

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
Some pin assignments looked great in the schematic and on paper, but clearly a few of them are in a sub-optimal order:

Will do some pin re-planning to make routing this a bit easier for myself. Getting to the DAC is the really shitty part...
 
Last edited:

Xian Xi

JammaNationX,
15 Year Member
Joined
Dec 1, 2005
Posts
27,748
You can always make it two sided, helps with routing but messes with mounting if the components are too big on the underside.
 

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
99aa748809a56837a65fd4a44972027e.png

12c765e85b8d587f1347cfbd432f0fd2.png
 
Last edited:

mikejmoffitt

Mickey's Coach
Joined
Feb 6, 2014
Posts
578
I have ordered the parts to populate the board off of Digikey. It takes about $30 in parts, brand new from Digikey, if you play by the "rules" (without a clone EPCS chip; once I find the correct clone it'll cut around $14 off the price!) I hope a board can be sold reasonably for $70, as I'd like it to sit in the price range that the NESRGB is in.
 

Xian Xi

JammaNationX,
15 Year Member
Joined
Dec 1, 2005
Posts
27,748
$75-100 is more than fair. SMD assembly is fun when you make less than 3 boards only...lol
 

fenikso

Slug Flyer Pilot
15 Year Member
Joined
Oct 6, 2004
Posts
3,932
Awesome, can't wait to see the final product assembled. Pricing seems very reasonable.
 
Top