Jump to content
IGNORED

Sophia rev.C - DVI board


Simius

Recommended Posts

It doesn't matter what is to blame, the thing is, if you really want to reach more monitors and even tv's, there is only 1 thing you can do. You can't change every monitor and tv, but you can tweak and tune the Sophia output. If you don't think that is possible or even needed, then the only way to fix this is getting a (expensive...) external scaler to process the Sophia output into something that is compatible with most monitors and tv's.

  • Like 2
Link to comment
Share on other sites

Compatibility issues exist with the Component video version as well. My LG M227WD (which basically works with every retro device thrown at it) refused to display a picture with the board I was installing in someone's machine, but a Samsung TV was OK with it.

 

Yeah, there are. This is a result of the properties of the image generated by the Atari system, we loves as it is. :)

 

There are two solutions - make some changes in the Atari system (troublesome and causing also other compatibility issues) or full image buffering, generated 16ms (NTSC) or 20ms (PAL) - significant - delay and additional costs.

Link to comment
Share on other sites

There's a special art to phrasing Sophia feature requests. If it's any consolation, it's a skill I apparently lack. :)

 

As far as I remember, you suggested an identification of the Sophia in the system. Impossible with current hardware because of lack of the bi-directional data buffers. Try again with some possible thing. :)

Link to comment
Share on other sites

Simius, i'm sorry you feel you are being attacked, i only want to help and find a solution. If i had the knowledge to do this myself i wouldn't be here asking all this questions... we can not do this without you. If there is some way to quickly change settings and trial and error, that would really be helpful.

  • Like 4
Link to comment
Share on other sites

Well I for one really like my Sophia Rev C so far. I haven't had time to install it in my 800 yet, but I look forward to seeing how great it looks on my 5:4 NEC EA193mi-bk 19 inch. I think its a totally acceptable expense to purchase a screen to go along with this great mod. Thanks Simius for this great product!

Link to comment
Share on other sites

i like it as well, dont get me wrong, and i also purchased an extra screen for it that works, on advice of Simius. But i would like to go the extra mile and make this work on my tv and projector as well, which im sure just needs some finetuning. If that works, the board can be used on almost any display, and will make it an even better product.

Edited by jowi
Link to comment
Share on other sites

 

As far as I remember, you suggested an identification of the Sophia in the system. Impossible with current hardware because of lack of the bi-directional data buffers. Try again with some possible thing. :)

Thanks for the explanation. It's an improvement on one-word answers or not being answered at all. You have a great attitude.

Link to comment
Share on other sites

I asked about the detection issue two or three times previously in another thread and the question was ignored once and given a curt rebuttal (something along the lines of 'Is not possible', to the best of my recollection) when a response was given. The question may indeed be irritating or dumb (I guess it's flat out impossible for the CPU to read the GTIA address space anyway), but I posed it in light of the problematic situation of extra functionality (V-Gate, hi-res colour, etc) being added after the fact, but without any means of software being able to detect it. The extra facilities are thereby only usable a) in immediate mode in BASIC (by issuing POKEs on a machine one knows is equipped with Sophia and with the correct supporting firmware), and b) if software makes a blind guess that the hardware/firmware is present and issues writes to it in the hope that they do something. The matter of V-Gate (which is supported by the 1088XEL U1MB firmware) isn't such a big problem, since if the setting does nothing, the user can probably understand why (if there's no Sophia in the machine). I was uncomfortable with that situation, but it's fundamentally no worse than Covox plug-in support (Covox being invisible to software too).

 

In any case: you've been kind enough to provide a clear explanation this time (probably I should have known reads from GTIA were not possible, but Michael St Pierre has designed an aftermarket Atari 8-bit motherboard and he seemed to think it was a design decision as opposed to a flat-out impossibility), and I won't bring the matter up again. Nor do I propose to lodge any further feature requests - possible or otherwise.

 

Sophia is a fine device, and asking what I consider perfectly reasonable questions is not intended as an implicit critique. What I suggested is not possible, and that's OK.

Edited by flashjazzcat
  • Like 7
Link to comment
Share on other sites

I ordered a cheap ($32) scaler from alixepress... just to see if that thing would 'understand' the Sophia signal: http://www.aliexpress.com/item/Universal-Digital-HDMI-to-HDMI-4K-Scaler-Converter-Amplifier-Down-Upscaler-with-Zoom-Aux-Audio-3D/32857250937.html... and to my surprise, i admit, it works pretty well. Connected in between the 600XL and the Acer monitor, which could not handle the Sophia signal, it now works almost perfect. Centered, scaled to 1920x1080...

 

post-66363-0-45697000-1543084101_thumb.jpg

 

The scaler itself is the size of a pack of cigarettes, in a heavy metal box. You can switch between 720p. 1080p, 4K resolutions, do some zooming. The scaling itself is not very high quality, but good enough to make the Sophia work on 'picky' monitors.

 

post-66363-0-73226700-1543084114_thumb.jpg

 

Also tested it on the 60" Pioneer Kuro, same result... in this case the scaler seems to do a better job, the image looks a bit better compared to the 24" monitor.

post-66363-0-44063100-1543084128_thumb.jpg

 

So, this is a cheap solution to fix the dodgy Sophia signal eeeh i mean those darn picky monitors that can't handle the Sophia signal.

I've also bought a 2nd hand Lumagen Vision HDP scaler, i expect the same results, but with better, near perfect scaling. Will post some more when it gets here. I hope by adjusting the timings of the Sophia signal using the Lumagen, i can get it to work even without having to scale it.

Edited by jowi
  • Like 4
Link to comment
Share on other sites

 

 

The scaler itself is the size of a pack of cigarettes, in a heavy metal box. You can switch between 720p. 1080p, 4K resolutions, do some zooming. The scaling itself is not very high quality, but good enough to make the Sophia work on 'picky' monitors.

 

attachicon.gifIMG_2623.jpg

 

 

I have a S-video to HDMI scaler made by the same company and comes in the same metal box. So, if you have to use a scaler, why not just use native S-Video (existing OEM monitor jack) and the S-video to HDMI scaler to get the same result? Also, if the Sophia does not use HDMI since it requires a licence, why not use display port or mini display port? It carries the same signals, is royalty free and you can buy a display port to HDMI cable for under $10.

Link to comment
Share on other sites

DVI is digital, svideo is analog, That should answer your question. Sophias output is digital, razorsharp and clean and without artifacts. There is just no comparison to svideo. Oh, and if you look at the pics, you will see a dvi to hdmi converter.

 

Again, if the signal from the sophia board was more compatible, this box wouldnt be necessary. Or you have to be lucky with a monitor or tv that can process it.

Edited by jowi
Link to comment
Share on other sites

Again, if the signal from the sophia board was more compatible, this box wouldnt be necessary. Or you have to be lucky with a monitor or tv that can process it.

That's my point. Why not have the Sophia output to display port or mini display port instead of DVI-D? There is no licence (royalty) like HDMI, but display port it is essentially HDMI ready. You just need a mini display pot to HDMI cable (Passive) and you have video and sound in a small package that goes directly to HDMI to your TV. Compatibility issue should be gone.

  • Like 2
Link to comment
Share on other sites

DP. uses an incompatible LVDS signaling protocol that runs at a far higher frequency (8-10 Gbit/sec rather than a top-end of 680 Mbit/sec for HDMI). Alas, it's only compatible because it can send an HDMI signal across the interface if it detects a passive DP->HDMI cable is attached, it's not natively compatible.

Link to comment
Share on other sites

For instance - the 1280x1024 resolution covers only normal width (40 characters/320 hi-res pixels) screen. Unfortunately, the resolution can't be switched. Can only be set in the core.

 

 

 

I ordered a cheap ($32) scaler from alixepress... just to see if that thing would 'understand' the Sophia signal: http://www.aliexpress.com/item/Universal-Digital-HDMI-to-HDMI-4K-Scaler-Converter-Amplifier-Down-Upscaler-with-Zoom-Aux-Audio-3D/32857250937.html... and to my surprise, i admit, it works pretty well. Connected in between the 600XL and the Acer monitor, which could not handle the Sophia signal, it now works almost perfect. Centered, scaled to 1920x1080...

 

If I were going to get a scaler to use with this, should I get the 1536x960 model instead so I can use modes other than 40 column, even though I have a 1280x1024 monitor? Is there a list of modes that are supported by each model?

Link to comment
Share on other sites

That's my point. Why not have the Sophia output to display port or mini display port instead of DVI-D? There is no licence (royalty) like HDMI, but display port it is essentially HDMI ready. You just need a mini display pot to HDMI cable (Passive) and you have video and sound in a small package that goes directly to HDMI to your TV. Compatibility issue should be gone.

I think there is a bit of a misunderstanding; the issues with Sophia's compatibility are not on a connector level, but on a signal level (or monitor level, depending on your perspective). You can use convertercables from dvi to hdmi, from hdmi to dp, from dp back to dvi and from dvi to dp, the signal will be 100% the same. It will not change. It will not solve any problems. The cables/converterconnectors are not active, and dp, dvi, hdmi all share the same signals and are interchangeable in this case. You can see in the picture i'm using a dvi to hdmi converter, since the scaler has only hdmi. My laptop came with a Mini displayport out, and a mini dp-to-dvi convertercable... besides that, dp is hardly used in consumer electronics. DVI is obsolete. HDMI is the way to go but requires license fees, so Simius' decision to use DVI is absolutely perfect and valid. He could have used a DP connector, but like i said, that would not have changed anything on the signal level. We would still have issues, an we would all need a dp 2 hdmi convertercable... the only valid argument for dp might be its size, so it would fit anywhere in our atari casing.

 

The 'dispute' i'm having with Simius is that he states that there is nothing wrong with the Sophia signal and all issues are monitor related, my point is that there is a timing issue with the signal, since some monitors and tv's accept it, but most wont. Now, since Simius is not inclined to make any changes on his side, we have to find a solution, and this is a very cheap solution. It is not ideal, since it scales the signal up to 720p or 1080p, adding slight artifacts, but in the process it also changes the timings so the signal can now be used on 100% of ALL monitors and ALL tv's EVERYWHERE, and it is still way better quality then SVideo.

 

I'm waiting for a better solution in the form of a professional scaler (a Lumagen Vision HDP, a bit older machine that can be found cheap). With a scaler like that you can actually change the timings (h/v front/back porch/pixels etc) while keeping the original resolution. Or, if you want to scale up to 1920x1080, it will do a much better job scaling then the cheap china box i mentioned above. The china box is a quick fix and (to me) proves that the issue is in the Sophia signal, but at least i can now feed the atari signal anywhere in my home entertainment, and even use it as a source for my 4K JVC projector. 120" projection screen with donkey kong, oh yeah ;)

Edited by jowi
  • Like 3
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...