Making the best clone system?

[5233]

I was wondering how hard it would be for some of the techies here to produce at least a 99% accurate genesis clone. I had some interesting ideas for one and have seriously considered attempting to get one made as a Genesis enthusiast, but I want advice from techies who know the hardware well and what it would require to make a quality clone. I'm interested in hearing from you if you can give any input on that, thanks.

[Bones Justice]

I remember they used to sell alternate cases for Sega Saturn back in the day. I always wanted to have a Genesis/32X/SegaCD with TeamPlayer inside one of those Saturn cases. I would like to have a simple, all-in-one solution that I could take with me because my original Genesis/32X/SegaCD unit is not at all portable.

[nieds16]

Some guy posted on ebay his all 32x/cd/genesis in a saturn case. He called it fusion. It is on youtube. He did some major, major work on the inside. I would never be able to do anything like that. Good luck on the project and keep us posted. I was thinking about trying to do something myself that is a lot more simplistic concept. I was thinking taking a CDX apart and using the 2 boards plus an extra genesis 2 board with a 32x stripped down and modded to be part of the board. You wouldn't be able to play the cd 32x games, but i honestly wouldn't care. Seems possible, but I will just have to see. I've been thinking about this for a while and I just bought a cdx today, yet it is untested so I'm not sure if it will work.

[slobu]

I guess it depends on what you consider a "best" clone system. I paired a AA battery powered Genesis clone with an Eye-Tech projector powered by a AA USB charger to play games off the grid. When the Mayan Calendar rolls over and all hell breaks loose I'll still be playing Battle Master

[Bones Justice]

Some guy posted on ebay his all 32x/cd/genesis in a saturn case.

I missed that. How much did it sell for?

I guess I wouldn't care if it was larger than a Saturn. Maybe the entire combo in one sturdy case. I won't take my combo on the road because it's just too awkward to pack and unpack. I don't have any idea how to take them apart and reassemble in one case, though. I do have a Genesis 3 but usually take my Nomad on the road instead because of Virtua Racing. I wish I could just plug a spare 32X into the Genesis 3, though, so that we could play Virtua Racing 32X and Virtua Fighter.

Good luck on your project!

[KillerBean2]

My take on a perfect clone:

HDMI output with perfectly scaled lag free 1080p picture and crystal clear audio.
WiFi/LAN connection for online multiplayer gaming.
Wireless controllers with micro switches in both D-pad and the buttons.

[Ace]

HDMI output with perfectly scaled lag free 1080p picture and crystal clear audio.

The HDMI would require a high-end RGB to HDMI converter integrated within the system. I'm sure that would make for one expensive Geniclone. Sound-wise, if a clone has a YM3438, it's a no-go for me.

WiFi/LAN connection for online multiplayer gaming.

I don't exactly see how this could be achieved.

Wireless controllers with micro switches in both D-pad and the buttons.

Now this would be damn nice. You'd just need to interface controllers compatible with the Genesis' controller signals via RF. In this case, something like the Generation NEX could be done: integrate a 2.4GHz RF receiver into the system and have two controller ports for using original Sega controllers.

Now for my take on a perfect Geniclone:

-Must have RGB, S-Video and Composite output (RGB MUST be through a 9-pin mini-DIN in order to mix the RGB output with a 32X)
-Must use a Yamaha YM2612 (discrete chip or ASIC implementation, I don't care, as long it's not the YM3438 like modern GOAC-based clones)
-Must be compatible with ABSOLUTELY EVERYTHING
-Must be able to use original controllers
-(optional) Integrated YM2413 you can enable/disable for Master System games (and it better not be made after 1993; YM2413s made after that year are usually clones)
-Must sound like a pre-VA7 Genesis Model 1 (no exception)

[KillerBean2]

The HDMI would require a high-end RGB to HDMI converter integrated within the system.

Now that would be silly. I'm talking about a complete redesign of the entire VDP and the sound chips. A completely new chip that takes the same commands as the YM7101, YM2612 and SN76489 and respects the delays and quirks of the original chips, but spits out high quality digital AV directly.

I don't exactly see how this could be achieved.

That's true. It's physically impossible. But it would be nice if it wasn't nonetheless.

[Ace]

Now that would be silly. I'm talking about a complete redesign of the entire VDP and the sound chips. A completely new chip that takes the same commands as the YM7101, YM2612 and SN76489 and respects the delays and quirks of the original chips, but spits out high quality digital AV directly.

I actually thought about that after I posted about the RGB to HDMI converter. However, I'm not sure how you could get digital audio out of the YM2612 and SN76489. I do believe you'd need to tap the signal from the YM2612 before the DAC (this would require an ASIC implementation of the chip), but I'm not sure if the SN76489 has some digital outputs inside the chip.

[Jorge Nuno]

I dont see why the VDP needs digital outputs, remember the analog video output only has 15 voltage steps in a span of 0-5V meaning that each step is like 300mV... For the PSG out it's roughly the same except its a log scale.

This means it's simpler to use an actual VDP instead of replicating it (which is impossible right now, no one knows how it performs internally except for some rough aspects).. One thing is emulating it's functionality in software, other thing is doing a clone chip implementation.


And yeah, I had this idea of doing a custom MD board (with real discrete 68k/z80/VDP/IO/FM chips) with those fancy features, but don't expect anything in the near future

[Mista_Ed]

im not sure what these guys are on about.....but my suggestions are

- beer can holder on the side of the unit
- colostomy / catheter function - ie: clone can go for a wee and poo for you (no more toilet-based interruptions!)

and...err.....yeh, thats all.

[AlecRob]

So, is someone actually going to make this thing?

[oldskool]

The perfect clone would only really happen if you purchased exactly the same processors that the Genesis had. Like the Motorola 68000 and the Z80. As long as the main processors were pretty much identical I think you would not be able to tell the difference. You would have to also try to clone the audio circuitry as close to the original as possible, or do something like the CCAM to it so that it puts out good tunes.

It seems like Sound is what most clones/emulators can't get straight.

[Ace]

The GOACs in today's Geniclones already have the 68000 and Z80 in them, but some GOACs are so cheaply made, they omit signals (TCT-6801) or have functionality that doesn't even work even though it normally would work (Master System compatibility on the TCT-6705 GOAC - pin B30 is connected to the GOAC, but Master System games refuse to work regardless of that). They seem to be based off TecToy's 580G GOAC, which means they all have a 68000, Z80, YM3438 (my big problem with GOACs as the Genesis originally came with the YM2612 and NOT the YM3438) and Sega's VDP (slightly different as the vertical overscan area and some solid color screens show up black).

Accuracy is not an issue on GOAC-based Geniclones. What is an issue is functionally and video/audio amps. Some Geniclones work with anything you throw at them (some even work with the 32X minus video mixing) while others have broken compatibility due to non-existent signals or signals that don't even work. Same with the audio and video amps: some Geniclones have really good video (although they all seem to have too much green in the video signal, most likely due to the amp as I know the TCT-6801 GOAC can have its excess green eliminated (at least on the RetroN3) by removing a certain pull-down resistor in the video amp) while others look absolutely disgusting (FC3 Plus Version 1 - VERY dark, smeared like hell and with horribly oversaturated colors), and in the sound department, some clones sound almost identical to original hardware (with the exception of filtering and Stereo sound in the case of the FC3 Plus Version 2 which is VERY close to a real Genesis, but has very weak bass and very strong high-end, and with the exception of slightly garbled PCM samples/low-frequency FM notes and PSG being slightly louder than normal on the RetroGen Adapter) while others are ALMOST there (the FC3 Plus Version 1 sounds REALLY good, but has no Stereo sound and when too much sound plays at once, it gets pretty badly garbled, but unlike most clones, low-frequency FM notes and PCM samples do not get garbled), and certain other clones don't even come close (the Gen-X and GN Twin come to mind as their FM is VERY badly distorted and the PSG is inaudible, and what to say of the MURDERED audio out of the software emulation-based AtGames clones? It's unbearable).

I think if Geniclone manufacturers can use a GOAC that's not half-assed (TecToy-580G, SM-801 - correct me if I'm wrong, but I believe both GOACs have RGB outputs) and get proper audio/video amps put together (like a modified version of TmEE's Audio Mod, which can work on GOACs with a few tweaks), we'd finally have a good Geniclone.

[oldskool]

Yeah that's what I pretty much agree with. Someone just needs to use a wish board and wire up a fully working Genny clone, then prototype the design using PCB CAD software and have a PCB maker make a couple. I would still rather see original IC Chips used and not glob tops, for some reason I just see them as better, maybe it's crusty old nolstalgia I don't know.

And keep it simple, just for enthusiasts. Use original controller ports and ac/rf/composite hookups. Don't worry about HDMI and all that other stuff, because then it wouldn't truly be a clone. Try to keep the functionality exactly the same as the originals.

If they would just duplicate the circuitry exactly like they did with the Flashback 2 - then it would be awesome.

I'm surprised no one has made a Genesis yet actually, considering the knowledge around here on them.

Of course this would have to truly be just for fun. The reason why I say that is because if you want a 100 percent working Genesis, just pay 10 bucks or whatever for a real one.