shmups.system11.org

Shmups Forum
 
* FAQ    * Search
 * Register  * Login 
It is currently Thu May 13, 2021 10:07 pm View unanswered posts
View active topics



Post new topic Reply to topic  [ 11 posts ] 
Author Message
 Post subject: Extron DVI-RGB 200 EDID
PostPosted: Mon Jan 06, 2020 4:21 pm 


User avatar

Joined: 31 Oct 2016
Posts: 1452
Location: bmore
Does anyone know these devices here?

I wanted to use one to convert a DVI signal to RGB to output to a 15kHz monitor, but I got confused when reading the manual's EDID section. The manual makes it sound like you have to connect a monitor to the pass-thru in order to output at any resolution other than the pre-programmed ones, and that monitor has to have an EDID signal to program the custom EDID bank.

However, I have the ability to force a signal over DVI that ignores EDID, and I'm sending it to a 15kHz CRT, so the monitor doesn't care.

The way I figure it, I have one of three outcomes here.

1) I can just hook it up and send a signal that ignores EDID and it works

2) I have to "spoof" the EDID by using a device of some kind (or possibly output from a PC?) to program the custom bank with my 15kHz EDID

3) This device can't handle the 15kHz resolution I want to send to it anyway and I'm wasting my time

Or maybe there's a #4 that I am ignorant of.

Thanks


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Mon Jan 06, 2020 5:09 pm 



Joined: 02 Mar 2017
Posts: 1261
I'm just taking educated guesses here, I could be completely wrong mind you, but EDID type stuff is almost always for communication between digital devices where it's a handshake of sorts saying "I'm a 1080p signal", then the display says "I can take a 1080p" signal, then it just works. Believe when you get to HDMI it can also be a sort of anti piracy type deal as well.

Anyway, with that device setup to output to RGBHV or RGBS, those type of monitors aren't going to care anything about the EDID - they don't even have the extra pins for non-video display type signals like even a common VGA cable has, so I'm guessing you'll be fine. I didn't even read through the manual but I'm guessing the EDID is for the passthrough only. Or maybe the device just needs a heads-up about what kind of signal it's getting (which my Extron CVC's need when converting - needs to know if it's a SD, EDTV or HD type signal via a manual dial).


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Mon Jan 06, 2020 6:56 pm 


User avatar

Joined: 31 Oct 2016
Posts: 1452
Location: bmore
Dochartaigh wrote:
Or maybe the device just needs a heads-up about what kind of signal it's getting (which my Extron CVC's need when converting - needs to know if it's a SD, EDTV or HD type signal via a manual dial).


Thanks for your input. :)

Yeah, that's what I'm concerned about. The DVI-RGB has an "EDID" selector wheel with pre-set output resolutions, and an empty bank that you can record the EDID of a monitor to (by connecting it to the local pass-thru output). The manual says, "The video source uses the bidirectional Display Data Channel (DDC) to determine the video resolution and refresh rate. The video source can obtain the rate directly from the local monitor or the user can select among 28 resolutions and refresh rates built into the interface."
There's a toggle-switch that goes between the selector wheel and the local monitor EDID.

If I take this at face-value, it means I have to load an EDID into the empty bank in order to get the device to output what I want. The manual never addresses a situation where your monitor doesn't have an EDID requirement.

However, based on my previous experience with Extron manuals, I would be willing to believe that if I have no local monitor connected, it will just output whatever I input. I'm hoping some Extron expert here might know for sure.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Mon Jan 06, 2020 7:43 pm 


User avatar

Joined: 06 Mar 2006
Posts: 12717
Location: Germany
You can simply set the EDID to the highest supported resolution (1200p I assume). The EDID data just needs to be present to allow DVI and HDMI outputs to switch to active when booting a system. Without an EDID present many video cards won't display an image after boot up.

For actual operation the EDID is irrelevant. The unit will convert your signal 1:1. If it works with 15khz signal remains to be seen though. There's certainly the possibility that it requires a 31khz signal as a minimum.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Mon Jan 06, 2020 8:21 pm 


User avatar

Joined: 31 Oct 2016
Posts: 1452
Location: bmore
Fudoh wrote:
For actual operation the EDID is irrelevant. The unit will convert your signal 1:1. If it works with 15khz signal remains to be seen though. There's certainly the possibility that it requires a 31khz signal as a minimum.


Thanks for info Fudoh.

I found a little mention of it here: viewtopic.php?f=6&t=59860&start=60

According to user cfx, the DVI-RGB 150 works, and using SOG is a safe way of sidestepping any sync voltage level issues (although my 2030 should be able to handle 5v ptp on the CMPT input)

I suppose unless Xer Xian has tested his 200 model with 240p content, there is no sample yet. :?:


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Thu Jan 09, 2020 11:42 pm 


User avatar

Joined: 31 Oct 2016
Posts: 1452
Location: bmore
I am happy to report that the Extron DVI-RGB 150 will happily pass a 240p modeline to my Sony PVM-2030 using sync on green. I think this one is a winner.

I'm using my Raspberry Pi 4 via HDMI output with a DVI adapter into the Extron.

edit: it appears that this particular extron device cannot handle full RGB (0-255) and must be set to limited (16-235). Seems okay to me for a 240p CRT image.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Fri Jan 10, 2020 12:30 am 



Joined: 14 Aug 2017
Posts: 1403
vol.2 wrote:
edit: it appears that this particular extron device cannot handle full RGB (0-255) and must be set to limited (16-235). Seems okay to me for a 240p CRT image.


This seems to be an ill that afflicts virtually all DACs, old and new. That said, isn't full vs. limited RGB only really relevant on flat panels? When I switch between full and limited on a CRT I can hardly tell any difference.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Fri Jan 10, 2020 4:34 am 


User avatar

Joined: 31 Oct 2016
Posts: 1452
Location: bmore
fernan1234 wrote:
vol.2 wrote:
edit: it appears that this particular extron device cannot handle full RGB (0-255) and must be set to limited (16-235). Seems okay to me for a 240p CRT image.


This seems to be an ill that afflicts virtually all DACs, old and new. That said, isn't full vs. limited RGB only really relevant on flat panels? When I switch between full and limited on a CRT I can hardly tell any difference.


Well, I won't claim to be an expert, but I think it can't possibly matter for a standard res CRT. The way I understand it, what's missing in 'limited' is dark levels between 0-15 and white shades between 236-255, which such a monitor can't resolve anyway. I believe it takes at least a PC monitor to get subtlety at those extremes.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Tue May 04, 2021 1:34 am 



Joined: 19 Mar 2017
Posts: 480
vol.2 wrote:
I am happy to report that the Extron DVI-RGB 150 will happily pass a 240p modeline to my Sony PVM-2030 using sync on green. I think this one is a winner.

edit: it appears that this particular extron device cannot handle full RGB (0-255) and must be set to limited (16-235). Seems okay to me for a 240p CRT image.


Would have thought all DVI based devices would have defaulted to full range.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Tue May 04, 2021 2:04 am 


User avatar

Joined: 31 Oct 2016
Posts: 1452
Location: bmore
strayan wrote:
Would have thought all DVI based devices would have defaulted to full range.


This particular device craps out if you force full range. This was a part of my experimenting with HDMI-VGA connectors when I got my Pi4.

I can confirm that output forcing full range worked fine with other devices, but DVI-RGB 200 displays garbage if you try it. Again, I don't think it will matter even one tiny bit for an SD CRT. Even if it shifts black up or down (can't remember which), you can easily compensate with screen controls.

Fernan reckons that most of these kind of devices would have been limited. I only have this one, the U-green (also only limited), the Tendak (have several major revisions but mine will do full) and the Portta (does full just fine).

But those other ones are all HDMI.


Top
 Offline Profile  
 
 Post subject: Re: Extron DVI-RGB 200 EDID
PostPosted: Tue May 04, 2021 1:07 pm 



Joined: 19 Mar 2017
Posts: 480
Does any know when limited range signals were adopted as a standard? Seems like buying devices made prior to this might be sensible?

Edit: my plan is to use one of these Extron devices to send the full range 640x480 signal from ultraHDMI to a 480p plasma and then send the RGB + Csync output to GBS Control for downscaling to my 15khz RGB SCART TV.

Edit 2: Hmm... anyone have any idea how much lag the buffered loop through adds? I can always just split the signal before it hits the Extron interface so I suppose it doesn’t really matter.

Edit 3: Well apparently the latest ultraHDMI FW update adds limited range output so there is that problem solved I guess.


Top
 Offline Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 11 posts ] 

All times are UTC


Who is online

Users browsing this forum: archimage, Brando1975, eatnooM, eightbitminiboss, energizerfellow‌, TooBeaucoup and 20 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Space Pilot 3K template by Jakob Persson
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group