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Possible?
My video output on my console is broken. I have to find someone who can mod it locally. The guy told me to bring it by when i get some money together. Instead of fixing the existing video output I would like to upgrade the picture is this possible?
yeah you can get an s video mod done but its a bit expensive
Genesis can't output component. It can output RGB, and component is very similar in quality, but they're not the same. I imagine that the only way to mod a Genesis for component would be to install a converter. It's easier to just get a SCART cable and an external converter.
I would rather go with RGB. I have a direct RBG input on my tv. How can i do this.. I must physically mod the hardware though, I will take it to a local expert.
If your in the US, that's probably a no-go if it's just VGA input on an HDTV. In europe and Japan, RGB inpust on standard TVs was pretty common (via SCART in Europe), so in that case you'd just need an SCART cable.
How do you know your video output is dead and not just the cable? (or were you using an RF box rather than AV cables)
Also note that depending on the version, the Genesis model 2 cannot be S-video modded due to the samsung-made encoder chip used (also quite poor in general), but RGB will still be present as it's what the system outputs natively. (available on the AV port on all models, with SCART cables available)
Guess I need a new Genesis. Still going to let the guy try to fix it. I have two different AV plugs and both had the same effect in the end, so its the output.
My TV says "RGB (PC)" on the connection. I use it to run my computer on my TV from my video card directly to the tv. Dunno if its the same RGB you guys are talking about on the Genesis, yes im in the US.
Thats good that you are not just going to through it away :)Quote:
Originally Posted by salamando
That's most likely the VGA input, not an actual RGB connection.Quote:
Originally Posted by salamando
Above the connection it specifficaly says "RGB IN (PC)", I have a thick cable running from there to the back of my computer, i guess it is called a VGA cable, not sure though. The picture is fantastic though i can tell you that. Its basically as good as HDMI. One step under it at the very least.
If it looks like this:Quote:
Originally Posted by salamando
http://dsnimg.dell.com/images/extern...VGA%20Port.JPG
Then it's a VGA port.
Well VGA is a RGB input... it merely has double the Horizontal sync rate than CGA, Scart, or just RGB + Sync over RCA or BNC.Quote:
Originally Posted by ApolloBoy
Fun Fact: The colecovision was the first console to capable of outputting component with out converters or chip replacement... before it was really standard! Honestly, the video chip has composite sync, difference from red, and difference from blue
I like how it has such ahead-of-its-time video hardware, but they didn't give it hardware-assisted scrolling.
Likely because of the cost involved in that.Quote:
Originally Posted by j_factor
Double NTSC/PAL sync rate and higher: 31+ kHz. (early VGA monitors do sync down to ~15 kHz for CGA/EGA compatibility, and thus can also accept RGB from Genesis, SNES, SMS, Amiga, Atari ST, etc)Quote:
Originally Posted by Dant
Not really ahead of it's time, at least no moreso than RGB output. The TMS9918 line used a YPbPr type color palette, thus it was most practical to output that other than native composite (as on th efirst models), doing so facilitated external composite video encoders for multiple video standards (PAL/SCAM and variations thereof). THe same goes for other hardware using that type of palette (often outputting composite and/or chroma/luma natively) like Atari's TIA/CTIA/GTIA (MARIA too I think), NES and such. (thus goign to RGB for th eplaychoise was somewhat awkward, and required a modified palette -or an onboard transcoder to convert YUV/YPbPr into RGB, I think it was the former though)Quote:
Originally Posted by j_factor
The SMS, Genesis, SNES, an dpretty much everything following that (along with most Arcade boards from the mid 80s onward) used RGB palettes and output that natively, which was then transcoded into other things externally from the VDC chip. (I seem to remember something about the Jaguar using another type of color space internally, but I'm not positive, regardless it did output RGB)
In that line, if RGB was so common in electronics, why did the US/NA end up using YPbPr and never adopting RGB input (other than VGA more recently)? With sync on gree you have the same number of wires used as YPbPr component video. (and both shoudl work fine for higher bandwidth video of higher resolutions, ie VGA)
It may be possible to mod it for S-video depending on the vidoe encoder used. You'll need to open up the unit and look on the board -or post a picture/scan. (also note the model revision for comparison - find out if you've got one of the later models with good sound)Quote:
Originally Posted by salamando
Also, the composite video may not even be bad, just the AV port might be damaged -which could also be repaired. If the entire video encoder somehow went bad you're stuck with RGB only then. (and external transcoding)
Are you absolutely sure it's the system itsself that's bad and not the cable you're using? You are using AV cables (with composite video -yellow- plus red/wite audio RCA connectors), right, not an RF adaptor?
one a bit related note, VGA at 31KHz is only for 640x480 signal, 800x600 for example is 36KHz, 1920x1080 is 65KHz....
Yeah, that's what I was aluding to with my first comment in post #14. ;)Quote:
Originally Posted by TmEE
That only refers to the horizontal sync rate though, that is 480 lines at 60 Hz refresh, vertical sync (and horizontal resolution) can vary without changing that. (and is th eonly thing variable on standard definition TVs -except some PAL -and SECAM? sets which can allow both 50 and 60 Hz refresh.
What about lower res VGA modes with signficantly fewer than 480 lines: like 384, 300, 256, or the common 240 or 200 lines. Do those still use the lower sync rate? Or did those use line doubling, or modifying the refresh rate to get into acceptable sync rate? (or only on later cards aimed at compatibility with newer monitors only syncing to 31 kHz?)
those lower resolutions are double scanned or given some overscan to get a "normal" amount of lines (400 or 480).
Because, it is nigh impossible to standardize anything in the U.S.. Do you realize how long it took us to switch to digital TV? We basically had to shove it down everyone's throat! In fact the only reason we got component in the first place was that it was standard on DVD players when they got started. DVDs use MPEG-2 which stores video just like component (this was for more efficient for storage as RGB would have taken up more space).Quote:
Originally Posted by kool kitty89
In an MPEG-2 stream you store colors in Y'CbCr, decode it to Y'PbPr and send it out to your TV to decode it to RGB.Quote:
Originally Posted by Dant
European DVD Players decode it to RGB on the fly and feed that to the TV.
- Either way, component allows to transmit a higher bandwidth than SCART, the connector used for RGB in Europe. A higher bandwidth (twice the bandwidth to be exact) is required to transmit 768/720/640x480 in Progressive Scan instead of Interlace.
A better alternative to Y'PbPr component would have been VGA.
We still had standards. Mind you competing standards but that's how the US is. If we didn't have standards, chances are the consumer electronics market would have suffered greatly. Just like in the early to mid 80s with the swarm of home consoles cashing in on the VCS's success. RF, Composite, S-Video, Component. You can find these on pretty much any AV device in North America, though S-Video and Component are harder to find which in itself is annoying since they are far better than RF and Composite.Quote:
Originally Posted by Dant
I still wish the Genesis had S-Video output like on the SNES. Almost all of my old consoles use S-Video, save for the 7800 and NES which are connected to an RF-only TV (still look pretty good though). Why must the Genesis be stuck in the past... :confused:
The Genesis outputs RGB right out of the box. All you need is a SCART cable.Quote:
Originally Posted by salamando
Like others have pointed out, the RGB port on your TV is most likely a VGA / PC port (great for Dreamcast and Wii, or to hook up your Notebook). It won't work with the RGB that SCART transmits (240 interlaced lines per frame).
To hook up your Genesis via component, you'd need a SCART cable and a RGB to Y'PbPr transcoder:
http://shop.ebay.com/yuv+scart
BUT you cannot be sure that your HDTV supports 240p via component, so I'd recommend this solution only if your TV of choice happens to be a regular old CRT based SDTV with component in.
If you want to hook up your Genesis to your HDTV, buy a SCART cable and one of these:
http://shop.ebay.com/s.html?LH_Selle...nverter&_rdc=1
Hmm I dont see the point of this discussion or is it because USA HDTV's dont have SCART? Atleast our all HDTV's have 2 or 3 scarts.
We don't have SCART.Quote:
Originally Posted by MEGADRIVE Jeroi
Why can't SCART just be used??? Just like YPbPr with different sync rates for different resolutions, RGB via SCRAT should as well, and work fine for HD signals, at least as fine as VGA. (which is analog RGB, just with a 31 kHz minimum hsync standard rather than 15 kHz of SDTV)Quote:
Originally Posted by Christuserloeser
Hell, DVI-analog (RGB for VGA compatibility) uses a common ground and composite sync, so only 5 pins are actually used. (RGB+Sync+gnd)
It's silly to have RGB SCART connections but only allow VGA to be used for HD stuff. (it'd be like having separate component video ports for SD and HD on an HDTV)
Not to mention the odd TV with component but not S-video ...Quote:
Originally Posted by Guntz
However, also note that all the common video standards in the US came about for similar reasons as YPbPr with DVD: Composite video for VHS, S-Video for SVHS. ;)
Of course, many devices were using "s-video" prior to SVHs being released, a large number of early home computers did and had monitors using such. (Atari 8-bit family and C64 for example) Still others used RGB, and thus output that instead. (like ZX Spectrum and Amstrad CPC)
I'm sure if
The composite video encoder isn't as sharp as SNES either (moreso with CXA1145 than the fujitsu encoder, and quite awful witht he samsung one of many model 2s)Quote:
I still wish the Genesis had S-Video output like on the SNES. Almost all of my old consoles use S-Video, save for the 7800 and NES which are connected to an RF-only TV (still look pretty good though). Why must the Genesis be stuck in the past... :confused:
I'd say it's because of the AV port of the SMS used and due to cost on the model 1. (the encoders can support it, hence mods, just a few added components needed) I'd say that with the Genesis being released in 1988 in Japan, and S-video being a very new standard, they probably didn't feel it was worth it. And on model 2s, they wouldn't include it due to cost cutting (SNES2 also removed RGB, S-video, but did have sharper composite unlike all but some of the latest model genesis units, most others having much inferior samsung chips, still others having the same encoders as the model 1s do)
The CXA1645 is especially simple to mod for s-video, only requiring a couple components. (just a couple resistors, and capacitors for full compatibility, though often resistors alone are fine)
Edit:
They probably could have dropped the DE-9 EXP port on the Model 1 and added an enhanced A/V out instead with relatively little cost difference -using a DE-9 port as well, or a DE-15 if they really wanted provisions for future use -or something else like a DIN-13. (and add Y/C and stereo audio, rather than having to go through the headphone amp)
In fact, if they ditched the internal RF modulator and just used external liek the JP MD or Model 2s, there could probably have been no added cost whatsoever, perhaps savings even with the RF box removed and the s-video amp taking up that space instead. (a transistor, a couple capacitors and a couple resistors)
9-pins would be somewhat limited though, 13/15 pin would be great, then that could be the standed A/V port for the model 2, include mono+L+R+Y+C+R+G+B+Sync+5V (gnd on the sleeve) and you could either combine Y+C to composite in the cable or use a dedicated comp vidoe pin as well. With 15-pins you'd have enought left over to later add YPbPr as well, and a pin to toggle between SD and HD signals -ie enable VGA as with DC. (or just leave that to the base unit/software -RGB would be used for VGA as well)
Is there a cheaper way to do this??
or just build a Componet PCB inside the Genesis
It's possible to make a RGB to YPbPr transcoder from discrete components, but not that simple, I think ooXxXoo mentioned that he was thinking about making a tutorial.
As for making it internal, sure, but I think I'd prefer to make an external adaptor that could be useful for other RGB devices. (namely other game consoles)
Take a look at:Quote:
Originally Posted by KnightWarrior
http://elm-chan.org/works/yuv2rgb/report.html
And segasonicfan's modified version:
http://www.freewebs.com/vgmods/arcadeworks.htm
I've got a schematic laid out in ExpressSCH and a board in ExpressPCB if you're interested (still needs to be validated and a few bypass caps added). I've never done any serious electronics before so it might hurt you more than help...
I've priced out the parts and just the passive components, connectors (RCA/Power), and ICs cost about $45. If you want to print the board through ExpressPCB it'll be I think $70 (minimum order, comes with 3 boards). Then you need an enclosure and wall adapter.. another $15? I'm wondering if you could just use the +5v out of the AV port and save on the wall adapter though.
Newark.com has all the ICs in DIP packages, btw.
I think I'm going to with the JROK RGB converter (http://www.jrok.com/hardware/RGB.html) and put it in my own enclosure.
http://elm-chan.org/works/yuv2rgb/rgb2yuv.png
That is the one you want, a no frills RGB to YUV circuit, composite and S-video require chroma encoding, the more complex part, and something these consoles already do onboard (hence s-video modding, except for the samsung encoder lacking separate luma/chroma pins)
With RGB and YUV being the only concern, only simple discrete components should be needed, though I don't think that diagram shows this. (it looks like some additional chips are used, but those may be very cheap anyway)
I think you might be able to use the +5v output by systems as the power suource (all SCART RGB outputs must have +5v, though multi-a/v out also often uses that for exteranl RF modulators). ooXxXoo did mention that -5v is also needed though. (so you'd need curcuitry for that onboard)
Edit: that second link seems to have a far more simplified version.
Segasonicfan apparently doesn't know about the CXA1645's use in the Genesis (VA3/4 model 2 and genesis 3) as he mentions the PSX and Saturn only.
I think I'll stick to S-video though, that should be plenty good (and a huge improvement over composite), the only problems for that would be those with Samsun'd model 2s. (all others are fine, with CXA1645s being particularly simple) Especially now that I know that using a larger resistor on chroma will elliminate the vertical line artifacting. (apparently ~480 ohms is ideal, I might go to 500 and use a single resistor though, probably OK, otherwise i'd need to chain some resistors together or use a potentiometer)
I'm not seeing how much simpler segasonicfan's is...with the exception of the power supply. I'd be interested to know the significance of his changes.
The ICs in elms:
One LM1881, Video Sync Separator
One 74HC4053;Triple 2-channel analog multiplexer/demultiplexer
Three LM6172; Dual High Speed, Low Power, Low Distortion Voltage Feedback Amplifiers
Looking at the board, JROK's version seems simpler to me. He's also included 3 trimpots.. I wonder if they sit right before the 75ohm resistor on the outputs. The chinese converters you can get on ebay have six trimpots in them. Someone commented on another forum that this indicates poor design.
BTW If you are playing on going into an HD TV: I've read reports that people are having trouble with 240p through component, but works fine through HDMI.
Hey, another interesting note about VGA RGB is that some HDTVs will in fact support 15 kHz VSYNC, see: http://www.atariage.com/forums/topic...apable-lcd-us/
I would assume this would also be with simple scaling, no deinterlacing. (not sure if the same TVs also support proper 240p via composite/s-video)
Okay, so I've got a jvc x'eye that I would love to have something better than the regular composite cables. From reading this thread, it sounds like my best/only option is to use a SCART cable coupled with either a scart to hdmi or scart to component cable? Would using a converter like that degrade the picture quality enough to render the whole thing pointless anyway? The scart to hdmi boxes look pretty expensive versus the component adapters...is the quality that much better for hdmi when you are going through adapters?
Anybody know the options in this vein for a turbo duo?
The component adapters are a good option for a CRTs. The HDMI upscaler is the much better solution when trying to hook your X'eye to your HDTV:
http://www.sega-16.com/forum/showpos...9&postcount=15
so the hdmi looks noticeably better than component on an hdtv, even with it going through adapters?
Doesn't the X'Eye have S-video built-in. (or am I thinking about the Wondermega, or totally worng entirely?) I thought one of those had standard RCA AV out and S-video.
just the wondermega
As HDMI is digital there's no additional loss.Quote:
Originally Posted by rift
It works like this:
RGB -> Scaler (converts Analog RGB to Digital RGB) -> TV (no additional conversion takes place)
Via composite/S-Video:
RGB (gets converted to composite/S-Video) -> TV (gets converted back to RGB, digitized and filtered before being displayed)
thanks for the info. From reading the other thread you linked, it seems like your preferred best option is to just stick to a CRT tv - am I correct? What is your home setup like?
Are you positive digital displays work in digital RGB color and not Y'CbCr?Quote:
Originally Posted by Christuserloeser
In any case, they still have to go through digital to analog conversion, whether they ned to deal with comb filtering, color interpolation, etc. (the chroma resolution is generally lower in composite/s-video anyway, and composite has additional luma articacts which can be improved, but not elliminated by good comb filters)
Y'PbPr on the other hand should be generally similar to RGB in that respect, granted the color still needs interpolation to RGB for CRTs and digital displays if they indeed use RGB colorspace for the display. Still, there should be negligable quality difference between straight RGB digitization and YPbPr digitization. (unless the converson hardware onboard the TV is undulely biassed towards one over the other -or the converter of the HDMI adaptor is superior to the TV's onboard converter)
Again, if you happened to get a 15 kHz VGA HD set, you can go straight through VGA for low sync RGB. (that is if VGA will work with CSYNC, and doesn't exclusively require separate H/V sync)
And not that I have a prefrence towards YPbPr as a high quality analog transmition standard, IMO it's kind of dunb that Northa American DVD players standardized with that rather than going straight for RGB instead. (a standard long established in Europe and Asia, and mandated in some countries -like France)
Of course, DVDs work in YCbCr colorspace, but outputting analog RGB really shouldn't be much more costly than outputting YPbPr (plus there's alreayd VGA standard for analog RGB in the US as well). Going straight to a VGA connector would have been best (far more elegant than the trio of RCA cables component uses, albeit sync on green could have used an identical arrangement if necessary). Of course, it would still be using 15 kHz vsync for SD sets rather than 30+ kHz for VGA standards. (and some HD sets do indeed accept 15 kHz via RGBm as I mentioned)
It's not liek the cases with composite and s-video being tied to VHS and SVHS respectively (albeit Y/C connections were used prior to SVHS's standardization to soem extendt, like on Commodire monitors using dual RCA cables for separate Y/C). Both VHS and SVHS were completely analog standards, as was Laserdisc (which used a composite video signal as well) With DVDs (and VCDs) it's all digital anyway, so RGB makes about as much sense as YPbPr. Ang anyone watching DVD (or any H.26x -and most digital video standard for that matter -most using YCbCr rather than RGB) on a PC via a VGA monitor (or an HDTV via a VGA cable) is goign through that type of conversion anyway.
Actually, for my family it was actually being decoded to RGB colorspace for the primary VGA display, then transcoded to composite or S-video to watch on our Sony (or later Sanyo) SDTV. ;)
And for many adopters of DVD back ~1999-2001 (and indeed later), in the US they'd be using TVs with composite or S-video at best for a while anyway.
I don't know... it just seems pretty dumb to no go with RGB standard with the advent of DVD players. (again, VHS/Betamax and SVHS are different matters)
Color CRTs work with RGB signals internally, using composite and s-video makes sense, being derived from analog broadcast transmition/encoding methods, and RGB had been a proliferous standard in both Asia and Europe for over a decade by the time of DVDs. (and indeed, at least in Europe, RGB via SCART was/is a popular output method for DVDs, as is VGA for current gen game consoles -starting with the DC technically)