need information on XNEO-1/XMD-2 concerning RGB...

Hi fellow board members,

I've recently got a XNEO-1 and a XMD-2 unit (basically the units, just with another connector, one matching the Neo Geo Out, one the Mega Drive/Gensis 1 output).

I don't plan to use the two units to get S-Video out of the two machines, as I've got RGB inputs on my TV and both machines have RGB out "out of the box".

I know that for the NG it's better to use the composite sync instead of the FBAS signal to sync the Scart/RGB picture. The MD on the other hand does not have a seperate sync pin (contrary to what many "mod" pages report), so the MD RGB picture is always a bit "structured" as long as you aren't using a sync stripper in conjunction with the RGB out.

My question now: both the XNEO-1 and the XMD-2 feature two RGB outs in addition to the S-Video out provided. One is a 15-pin MSX RGB out and the other one is a 8pin DIN RGB out (should be same as used on the MSX machines a decade ago), which happens to be the same connector as the NG itself has in the back.

Has anyone tested those RGB outputs ? Is there ANY advantage of using the 8pin DIN RGB out on the XNEO-1/XMD-2 instead of directly plugging a RGB cable in the systems (NG/MD) ?

Does the 8pin RGB out on the XNEO-1/XMD-2 feature a "clean" composite sync out for brilliant colors or just FBAS for syncing the picture ?

I could test it myself by soldering a MSX->SCART cable, but maybe someone on this board has got any idea about that ?

Any help is highly appreciated

Thanks & Regards,
Fudoh

I can only speak to the XNEO-1, but it is a pure passthrough on the RGB. The Neo outputs a native composite sync signal, which is also just passed through. You are getting no benefit out of going through the XNEO-1 for Neo Geo RGB output.

I have no idea about Megadrive one.

ChrisR

Chris,

thanks, sounds reasonable to me. Do you know if I'm right to assume that the 8pin DIN out on the XNEO-1 unit is basically a MSX style RGB port (as it's listed in the hardwarebook for example) ?

Thanks & Greetings
Fudoh

I had always asssumed the 8pin port was there to function as a pass-through for a regular Neo Geo AV cable.

What the XNEO-1 does is take the RGBS + 5V from the back of the neo and do the svideo conversion on-board, with a chip that is meant to output svideo natively. This is the cleanest svideo you can get, a definate stepup from a mod. There is just no way you can expect the RGB converter chip on the neo to output the best svideo possible when you are just building something to amplify the weak signal it produces, not to mention the missing BPF and delay.

I have never used the 8pin din or the 15pin RGB ports on my units, I always used just the standard svideo and stereo outputs. Looking in the manual, it seems to be the 8pin is for connection to the standard Neo Geo SCART cable.

Thanks,

ChrisR

Actually, the XNEO-1 uses the same decoder chip as the Neo uses (CXA1145), so the quality is not *better*. In fact, on older Neo systems, you will end up with a darker picture with the XNEO-1 -vs- the internal mod.

Jeff

JEFF!

Pop on irc (you know where, hehe) someday man, I gotta talk to you!

Cya!

Daemon

Lik-Sang.com is selling a nice device, costs about $5

It converts scart to s-vid/composite and vice versa... pretty versatile to say the least