Sophia rev.C - DVI board

[_The Doctor__]

what? I though he provided a path for artifacting....or did I just jumble up projects in my head again?

[Faicuai]

Image ovality and differences resulting from the properties of NTSC and PAL systems are a disadvantage, not a desirable feature. Tolerated because it is indelible. So far.

 

From an pure / absolute point of view, yes, you are correct.

 

But considering the historical value / weight of our experience, the name of the game here is FIDELITY. Or, in other words, an as FAITHFUL reproduction of our user experience as materially / technically possible.

 

Most past software titles (which make up the vast majority of Atari's SW library) were coded with these machines visual properties' in mind. Therefore, if we are not able to recreate such visual properties, we can hardly re-create the original experience itself. This is a problem within NTSC itself, as color-decoding for this standard actually changed, and so the actual color palette extracted from the Atari (very hard to reproduce accurately, indeed).

 

For instance, some software like Flags of Europe and Summer Games, somehow thought that that it was a good idea to source red color for the flags from the LAST vertical row of the color palette, specifically patches #1 or #2 from left to right (instead of true red-primaries located way above and closer to the first rows). But, as it turns out, that last row is VERY, VERY hard to decode accurately with modern NTSC electronics (as it used to look on early days), no matter how much you (mindfully) fiddle the color pot AND the color phase (hue) adjustments.

 

The bottom-line is NTSC is not and will not be a 1:1 output aspect ratio. It is shrunk horizontally by a factor of (pretty close) 11/12.

 

In any case, if the machine still outputs its native COMPOSITE and Y/C output while Sophia is working (and all outputs are routed through a decent, powerful video processor), this discussion has no real impact or relevance, anyway.

Edited August 19, 2018 by Faicuai

[Frankie]

 

In any case, if the machine still outputs its native COMPOSITE and Y/C output while Sophia is working (and all outputs are routed through a decent, powerful video processor), this discussion has no real impact or relevance, anyway.

I guess you could always install a UAV along with it, then you get all three output with excellent quality,

[MagicMarc-er]

Does anyone know what type of connectors are used on the ends of the ribbon cable that is supplied with the Sophia board? I have been trying to find a longer version of the same thing because, depending on where you mount Sophia inside a 1200XL, the ribbon cable could stand to be a few inches longer. I've been searching around on ebay but can't seem to find that type of connector.

[jc13]

Does anyone know what type of connectors are used on the ends of the ribbon cable that is supplied with the Sophia board? I have been trying to find a longer version of the same thing because, depending on where you mount Sophia inside a 1200XL, the ribbon cable could stand to be a few inches longer. I've been searching around on ebay but can't seem to find that type of connector.

 

Attached image is what I ordered from DigiKey... If just making a new cable, you won't need the 2nd one.

[MagicMarc-er]

 

Attached image is what I ordered from DigiKey... If just making a new cable, you won't need the 2nd one.

 

Thanks! I also found part number A128014-ND, which is a 250mm (approx 10") cable with the appropriate connectors. I think the ribbon cable that is provided is 200mm (8") so this might be 2" longer. If I go with the A99461CT-ND connector that you showed, is there a specific type of ribbon cable that needs to be used or will any 10 position cable work?

[jc13]

 

Thanks! I also found part number A128014-ND, which is a 250mm (approx 10") cable with the appropriate connectors. I think the ribbon cable that is provided is 200mm (8") so this might be 2" longer. If I go with the A99461CT-ND connector that you showed, is there a specific type of ribbon cable that needs to be used or will any 10 position cable work?

 

 

I just used an old IDE drive cable and split off 10 conductors. Not sure if you have a way to crimp the connectors (I used a bench vise with some wood spacers to keep from destroying the connector), but if that's a concern I'd get the cable assembly for sure assuming it's long enough.

Edited August 23, 2018 by jc13

[adamchevy]

I am very impressed with this mod and I look forward to placing an order for my 5200. My 5200 was already previously Svideo modded by electronic Sentimentalities. I know the Svideo mod requires soldering onto the GTIA. Has anyone tried installing the DVI mod inside a previously modded 5200? I think it would work fine just putting the soldered GTIA in to the Sophia. I am curious if anyone has tried this yet. It might even clear up the Svideo signal?

Edited August 27, 2018 by adamchevy

[+mytek]

I am very impressed with this mod and I look forward to placing an order for my 5200. My 5200 was already previously Svideo modded by electronic Sentimentalities. I know the Svideo mod requires soldering onto the GTIA. Has anyone tried installing the DVI mod inside a previously modded 5200? I think it would work fine just putting the soldered GTIA in to the Sophia. I am curious if anyone has tried this yet. It might even clear up the Svideo signal?

 

Should work. I use this board on a UAV modded system without any issues. Sophia is designed to work in harmony with the GTIA chip, so any 'standard' video enhancement should work the same as always.

[adamchevy]

 

Should work. I use this board on a UAV modded system without any issues. Sophia is designed to work in harmony with the GTIA chip, so any 'standard' video enhancement should work the same as always.

[MagicMarc-er]

I've made some great progress and will post some pictures of my mod soon. Sofia works great and picture is incredible. I have only one remaining issue and that is sound. To the monitor port, I connected a Din 5 Pin To 3.5mm Male Stereo Jack Audio Adapter Cable. This I used to connect to some standard powered computer speakers and also to a pair of headphones. I can hear the sound but, even at maximum volume, it is very quiet. When I connected to a standard tv using the RF connector, the volume was fine. What am I doing wrong?

[+kheller2]

Was that a custom built cable? Didn’t think such a cable existed.

[MagicMarc-er]

Was that a custom built cable? Didn’t think such a cable existed.

Yes. I found it on ebay for about $6.50 (U.S.).

 

Sent from my Pixel 2 XL using Tapatalk

[adamchevy]

Does anyone know if the Sophia supports 144hz monitors? I’ve been looking into getting one because it looks like they would be better for most of the arcade style games I love on the 5200. Also, does it support DVI-D(dual link)?

[killersquirel]

How much are the Sophia DVIs going for? Are they still available?

[Simius]

Does anyone know if the Sophia supports 144hz monitors? I’ve been looking into getting one because it looks like they would be better for most of the arcade style games I love on the 5200. Also, does it support DVI-D(dual link)?

 

Sophia board required 50Hz (PAL) or 60Hz (NTSC) v-sync range monitor with DVI-D single link.

[Simius]

How much are the Sophia DVIs going for? Are they still available?

 

 

 

Yeah, Sophias are still available. Ordering info on PM

[+slx]

Does anyone know if the Sophia supports 144hz monitors? Ive been looking into getting one because it looks like they would be better for most of the arcade style games I love on the 5200. Also, does it support DVI-D(dual link)?

Why would you need that? Your Atari cant produce more than 60hz anyway, nor will it use a resolution that would require dual link to send to the monitor. If your monitor supports 144kHz it will happily accept the Ataris 60.

[adamchevy]

Finally had some time to give this a try. Wow! It looks great! Thanks so much for making this!

 

This is at 1600x900 at 60hz

 

This is on a Dell U3011t Monitor.

Edited September 19, 2018 by adamchevy

[jowi]

800XL_DVI.jpg

 

How did you mount/fix the dvi connectorboard on the inside?

[Ffin72]

How did you mount/fix the dvi connectorboard on the inside?

It looks like it's been soldered in place of the rf unit. I'm more interested in learning how he cut such a neat hole, that's a fantastic job.

 

Sent from my SM-G900F using Tapatalk

[jowi]

I installed the DVI board today and connected it to an Acer 1920x1080 monitor, expecting it would scale the output to fit the screen, but it doesn't:

If i set my mac mini to e.g. 1600x900 or 1280x720, the acer scales it to fit 1920x1080.

It looks like it places the Sophia output at the left top of the screen. My Pioneer Kuro 600M (basically a monitor as well) does the same.

Also, the Acer pc monitor shows the input as 1600x1200, while it should be 1280x960 (i've asked Simius about this as well in a pm).

I'm a bit confused about why both screens won't scale the output to 1920x1080?

Also, when i route the DVI output through my Arcam receiver and i try to open the Arcam's (overlay) menu, it won't show. Looks like the Arcam, and the HDFury Vertex that are behind it, can't cope with it either? The Vertex won't even show the basic resolution and info on the signal at all in it's OSD, or the OSD can't get itself to overlay as well, like the Arcam?

 

Edited November 1, 2018 by jowi

[+Spaced Cowboy]

You might find it's the Mac Mini doing some of the work behind the scenes. The Mac has a deferred rendering video infrastructure, so all graphics are composited together before being sent to the video interface. This allows it to do things like on-the-fly-scaling without needing to tell you about it. A lot of software will render at 2x the screen resolution and scale down at the point of output to provide anti-aliasing, for example. The GPUs are so powerful you don't even notice.

 

DVI/HDMI connections involve a conversation that takes place as the electrical link is training up to its full speed - in which the source gets to say "Can you accept *this* resolution, and the monitor says "I can accept *these* resolutions" (which may or may not include the requested one). Some monitors have built-in video-scalers, and can accept pretty much anything, some don't scale at all, and just know how to manage a fixed set of resolutions.

 

Or it could be something with Sophia - the only point I'm making is that the problem-surface is a lot larger than you might imagine

 

Simon.

[jowi]

I agree it can be many things. But i do get the feeling something is not 'right' about the videosignal the DVI board is sending. I hope Simius/Jacek can explain some more.

I connected the Sophia directly to the Vertex to see what vertex thinks about the input... it can't read it either (Port0, RX0), says 50 RGB 8 bit 113Mhz, where 50 is 50Hz, usually it says something like 1080p50, now only '50'. It regards the signal as a 'USER_FORMAT'. My gut feeling is that the signal needs some tweaking/timing/handshaking to make it look like a standard VESA signal? But again, this is something Jacek hopefully can explain.

Edited November 1, 2018 by jowi

[jowi]

This picture shows that the 1280x960 output from the DVI board is placed at the top-left of the actual 1920x1080 canvas:

Edited November 1, 2018 by jowi