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Yurkie

HDMI ColecoVision Mod

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Although I am not really fond of the idea of modding a ColecoVision. I feel it takes away from the original feel of playing it, plus the appearance of the console itself.

 

That said, if you want to Mod the a/v, why mess around with old composite and s-video... why not just go for HDMI

 

I have seen the instructions online for doing a/v mods, but none for HDMI, wouldn't a nice clean modern one female HDMI jack on the back look nice and be practical for many years to come?

 

I guess what I am asking is if any of you smart ColecoVision Modders would care take a shot at this and post instructions.

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You probably end up connecting the s-video (preferable yuv/rgb) to an s-video to hdmi device since hdmi technology is really advanced.

 

Converting something to hdmi doesn't mean it will improve quality. Modding an colecovision and pick up the s-video signales before they are combined to a composite signal does mean the quality will be improved.

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You probably end up connecting the s-video (preferable yuv/rgb) to an s-video to hdmi device since hdmi technology is really advanced.

 

Converting something to hdmi doesn't mean it will improve quality. Modding an colecovision and pick up the s-video signales before they are combined to a composite signal does mean the quality will be improved.

 

I know the quality of picture is limited due to the resolution. An HDMI receptacle on the back of a colecovision would be modern and supported for many years on the new T.V's

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Right, but the colecovision doesn't have everything needed to connect to the jack. In fact I'm pretty sure you need to create a circuit just to get s-video. You can't just make jacks all willy nilly, does it even make sense that a colecovision could support a cutting edge, high definition connection?

Edited by Spazmonkey

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Right, but the colecovision doesn't have everything needed to connect to the jack. In fact I'm pretty sure you need to create a circuit just to get s-video. You can't just make jacks all willy nilly, does it even make sense that a colecovision could support a cutting edge, high definition connection?

 

I am pretty sure that it can be done. I believe doubledown told me he took a poll, for s-video or HDMI Mod.

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It can be done. I've modded a ColecoVision to output VGA, and the difference is most definately noticable. The standard 256 x 192 resolution of the console is upscalled to 640 x 480, and the benefits of the extra resolution definition are clearly visible. I had started a thread somewhere here with screenshots of the console's RF, Composite Video, and VGA outputs for comparision. If you find the old thread, look near the middle or at the end of the thread for the screenshots of Montezuma's Revenge, and you'll see what I mean. The same modification could be done with an HDMI output, and the output resolution be it 480i, 480p, 720p, 1080i, psuedo 1080p, or 1080p would be dependant on the upscalling circuit used. The audio could also be transmitted through the HDMI cable as well, again depending on the upscalling circuit used. I chose VGA for my mod, because the poll I took for the upgrade choice, put VGA ahead of HDMI by the voters here. I think the choices in my poll were VGA, DVI, or HDMI.

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Hi yurkie,

 

I've tried two component to HDMI converter boxes, with very limited success. One converter box worked, but the picture was in 16:9 format, and a little short (!), neither of which is a good thing. My TV was unable to make the picture narrower, to a 4:3 format.

 

It did, however, make the picture more consistent across different TVs (I'm guessing, because I've only tried it on my TV!). With component video, the picture is good on some TVs, but on my TV, I get some vertical colour banding (easily visible in the "red" and green in Smurf's Rescue). Good enough for me, but not good enough to sell to anyone. With the converter, the banding is gone.

 

The other converter box didn't work at all. I haven't had a chance to figure out why, although I'm guessing the results won't be any better than the other box.

 

The quest continues, however. More parts on order, and experimentation to follow... in a few weeks, after my vacation... . :)

 

Thanks,

5-11under

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I know the quality of picture is limited due to the resolution. An HDMI receptacle on the back of a colecovision would be modern and supported for many years on the new T.V's

 

I am not convinced that HDMI is better picture quality-wise (1080i and below) than either 3 or 5 channel component. In fact their are many tests that show it's a bit worse. Audio-wise the HDMI spec is no better than optical or digital audio cable connections. Yes, you get the convenience of audio and video in 1 cable, which is a huge selling point to the masses, but the true purpose of the technology is mainly digital copyright (audio and video) protection crapola....

Edited by JL

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The same modification could be done with an HDMI output, and the output resolution be it 480i, 480p, 720p, 1080i, psuedo 1080p, or 1080p would be dependant on the upscalling circuit used.

I would stick to the colecovision's resolution, since the tv has to scale it back to its panel resolution. Otherwise chances are that the picture is scaled twice which is not good.

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That's is the thread. Look at Panama Joe in the Montazuma's Revenge pics. With the VGA you can distinctly see the buttons on his shirt and his eye, a lot better than the RF and even Composite. Not to mention the definition of the mortar lines in the bricks.

 

I challenge component video providing a better picture than HDMI, but again it depends on what resolution is being provided. 720p through component video cables, should look near exactly the same as a 720p output through an HDMI cable. Seemingly the only benefit would be the digital rather than analog signal. The only real benefit is if the HDMI output was 1080p which cannot be transmitted through analog component video cables.

 

The assumption about the audio is correct, as digital audio via Toslink, or S/PDIF should remain the same as digital audio through an HDMI cable.

 

With the output scaled to VGA at 640 x 480 displayed on a monitor capable of the resolution, the picture is definately better than the standard 256 x 192 on the same monitor, as displayed in the pictures in the above linked thread I had started a whiles back.

 

The ColecoVision to any high definition output mod is very easy upon determing which scalling circuit to use that will accept the stock VDP signals and provide the desired output termination. The hardest part is to stuff it into the console rather than having something external and multiple power supplies.

Edited by doubledown

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With the output scaled to VGA at 640 x 480 displayed on a monitor capable of the resolution, the picture is definately better than the standard 256 x 192 on the same monitor, as displayed in the pictures in the above linked thread I had started a whiles back.

Then the scaler of the VGA converter is probably better than the scaler in the connected tv.

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The ColecoVision to any high definition output mod is very easy upon determing which scalling circuit to use that will accept the stock VDP signals and provide the desired output termination.

 

Does the colecovision provide digital video signals?

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I really appreciate all the feedback you guys are giving. If you know any modders, please send them a link to the thread.

 

If someone wants to do the R&D but not give away their work, perhaps they could make a board with HDMI socket on it, and install instructions and sell it as a kit.

 

I saw a guy on here, in another thread that was selling a kit for the Atari.

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Does the colecovision provide digital video signals?

 

Not from the VDP no, they're analog.

 

As for a "kit" to HDMI mod a ColecoVision, I'd be surprised if someone would create one. The work can definately be done, but you're probably talking a couple hundred dollars for the installation of the modification. Even as a "kit" I don't see someone selling something like this for 20 or 30 dollars.

Edited by doubledown

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The Colecovision VDP outputs component video. Is there an easy way to just solder onto those pins? Do the levels need to be brought up or down to a level a TV can utilize? If so, how?

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The Colecovision VDP outputs component video. Is there an easy way to just solder onto those pins? Do the levels need to be brought up or down to a level a TV can utilize? If so, how?

 

Adjustments need to be made to these signals, and as far as how the lines need to be altereted, it depends on what kind of tv it is going to be connected to. If these signals are properly adjusted and used, then you are still only achieving a resolution of 256 x 192, but definately a clearer picture than you would get than S-Video, Composite Video, and RF.

 

This console was modded with:

Component Video

S-Video

Composite Video

Digital Optical Audio

Digital Coaxial Audio

Analog Audio

Internal Power Supply

 

supercolecorear1nq.jpg

Edited by doubledown

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I think those only work with progressive scan component video not interlaced; I could be wrong though. Even if it did work, all you would achieve is the standard 256 x 192 resolution, through an HDMI cable, no upscalling would be accomplished.

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I think those only work with progressive scan component video not interlaced; I could be wrong though. Even if it did work, all you would achieve is the standard 256 x 192 resolution, through an HDMI cable, no upscalling would be accomplished.

 

You aren't going to get better quality by increasing the display resolution over the source's native resolution. Sure, you can line double, pixel replicate, and filter and process to your heart's content, but the source is still 256 x 192, and the truest representation of that source is on a monitor that can display that resolution unaltered.

 

If I'm not mistaken, the ColecoVision's VDP outputs a color difference signal (Y [b-Y] [R-Y]), so the best signal you can get from that would be YPbPr ("component video"). Feed that to a standard resolution CRT TV with component inputs and that is as good as you are going to get (and it will be very good). The only thing better would be if the CV's VDP could output RGB, and then you could feed it to a standard resolution (15 kHz) arcade monitor (or other form of standard resolution or multisync RGB CRT monitor), and that would be perfect; as well as being viewed on the intended display device (15 kHz CRT).

 

The course dot-pitch and course triad shadow mask, along with the general characteristics of the phosphor in a standard resolution CRT all combine to create certain effects that the original developers of these games counted on. These effects include softening and blending of color transition points. The softening effect also helps blend stair-stepping. For example, in the arcade game Pac-Man when viewed in its original intended form, Pac-Man appears round, as do the power-up pellets in the corners, as do the dots you eat. The Ghosts appear to have a rounded and smooth shape as well. The text in the game does not look like a series of jagged, stair-stepping lines; but rather; smooth, curvy lines. These old standard-resolution video games look horrible on high-resolution displays. Anyone can see this for themselves by firing up an emulator and playing the game in full-screen mode to see how the games look on their high resolution PC monitors. You'll see one of two things; either razor sharp edges to every object, full of ugly jagged stair-stepping (this is done with basic pixel replication resizing), or an artificial looking, pasty, hazy smoothing effect, which is done via filters/processing. Neither effect is pretty.

 

Here is an example of one can expect with "upscaling" an old standard resolution video game to display on a high resolution monitor:

 

Pixel Replication (unfiltered):

 

3844790916_89e4473847_o.png

 

Upscaled with bilinear filtering:

 

3844790758_62d58a90ca_o.png

 

Native resolution on 15 kHz RGB CRT monitor:

 

3844790900_769fa22335_o.png

 

I used SPO as an example because I happened to already have a picture of it displaying on an arcade monitor. Also keep in mind that the picture was taken with a cheap digital camera and the arcade monitor is well worn; i.e., losing its ability to have good focus; has weak reds, and some significant screen burn; but it still illustrates the general idea.

Edited by MaximRecoil

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