[SOLVED] Videogen: creating a 1080p modeline

[pfnuesel]

Hi all

I was so stupid to buy this this VGA to HDMI converter.

It says easy connectable, no software needed and lots of other ********.

However, I tried now for several hours distributed over several days with several computers and several operating systems (unfortunately not with several TV's).

I never got it working. I think I should send a 1080p signal to the VGA, which means a frequency of 60 Hz and a resolution of 1920x1080 (not sure about this).

I used this guide to do this. I installed videogen but I don't know how to properly define the 1080p modeline and also not how to bring this modeline to the VGA port. Can anyone help me?

You may have noticed that I don't have a clue about this multimedia stuff. All I want to do is have my computer screen on the television.

I appreciate any help!

[PabloTwo]

My LCD flat panel TV has various input ports, including 4 HDMI ports. In order to use any of the various input ports I must use the TV's remote control to select which input port to make active. This may seem obvious, but have you switched your TV's input port to the HDMI port that the VGA>HDMI converter is connected to?

[jpollard]

The specs don't support 1080p on the VGA:

# Video resolutions:
# VGA: 640 x 480, 800 x 600, 1024 x 768, 1280 x 720, 1280 x 768, 1280 x 960, 1280 x 1024
# DTV/HDTV: 480i/480p/576i/576p/720p/1080i/1080p

so the closest you will get is 1280x1024, 1280x768, or 1280 x 720.

Now it does look like the device will resample to 1080p, but that is not the input.

[pfnuesel]

Hi Pablo

Thanks for your answer. Yes, I checked that I am on the right "channel". I also double checked that by using another input on the same HDMI cable which I can see on the TV.

I googled alot about this problem, it seems that I need to feed this converter with the correct input, for example 1080p (but others are supported as well).

---------- Post added at 06:49 PM ---------- Previous post was at 06:47 PM ----------

It does need to be 1080p, also other inputs are supported, for example 1280x1024. But how do I send this signal to the VGA?

[PabloTwo]

To address your original question (how to generate a modeline?), in Linux you can use the cvt command. There are other programs that can do this also. So, say I wanted to generate a video modeline for a resolution of 1920x1080@60Hz. In a terminal window:

BASH:~/-> cvt -v 1920 1080 60
# 1920x1080 59.96 Hz (CVT 2.07M9) hsync: 67.16 kHz; pclk: 173.00 MHz
Modeline "1920x1080_60.00"  173.00  1920 2048 2248 2576  1080 1083 1088 1120 -hsync +vsync

Normally, the modeline would be used in your /etc/X11/xorg.conf file, which can be used to instruct your video card what which mode (resolution, etc.) to use. Of course, your video card must be able to support whatever mode your asking your video card driver to use.

You don't really give much information on your situation, such as, is the TV receiving any signal from the PC at all? If it is, is it that it's just not at the resolution you want? What video chip/card are you using and what driver is in use for it?

---------- Post added at 12:55 PM ---------- Previous post was at 12:50 PM ----------

Originally Posted by pfnuesel

It does need to be 1080p, also other inputs are supported, for example 1280x1024. But how do I send this signal to the VGA?

You just need to adjust your DISPLAY settings to which ever resolution you have available. Depending on whether you're using Gnome, KDE, XFCE or something else, just use your applications menu to find the configuration program to adjust your display, usually titled "Display".

---------- Post added at 01:02 PM ---------- Previous post was at 12:55 PM ----------

Also, from the command line, you can enter the command xrandr to get a list of currently available video settings you can use.

[CronoCloud]

It also helps to know the TV's native resolution, for example my TV was labeled 720p/1080i, but it's actually 1440x900 native. Check your TV's manual for details...once you know that, generate a modeline for xorg.conf.

CronoCloud

[pfnuesel]

Thank you all for your help. Sorry for not giving enough information at first place. I don't have a signal on the TV, at least I can't see something. I am using Fedora 15 with Gnome 3.

I tried to create this modeline, it seems to work, but I don't know how to use it now. I don't have the xorg.conf in the place you mentioned. Do I need to create it? What format?

When I go to Displays, I see an unknown display. Good thing is, that the TV changes the channel automatically to HDMI when I do that, so it seems to get a signal. However, I can only choose 1024x768 and 800x600 as a resolution for the TV. The TV itself is named as "unknown". Whatever I choose, I don't see anything on the TV.

xrandr gives me a list of resolutions, but not sure how to use them.

And last but least I don't know the native resolution of the TV and I don't know how to find out. No manual available.

[PabloTwo]

I'm not really sure how one goes about dealing with a TV as an output device rather than a regular PC monitor. But to answer you question regarding the xorg.conf file: Recent versions of the Xorg server included with recent releases of Fedora no longer require an /etc/X11/xorg.conf file to be present. That file used to be mandatory. You can easily generate one though:

su
enter root password
Xorg -configure

-configure
When this option is specified, the Xorg server loads all video driver modules, probes for available hardware, and writes
out an initial xorg.conf(5) file based on what was detected. This option currently has some problems on some platforms,
but in most cases it is a good way to bootstrap the configuration process. This option is only available when the server
is run as root (i.e, with real-uid 0).

There are endless examples on the internet of xorg.conf files. Here is one I grabbed from a Goggle search showing how/where to use the "modeline":

Section "Monitor"
  DisplaySize  332 207
  HorizSync    32-48
  Identifier   "Monitor[0]"
  ModelName    "ZV5000"
  Option       "DPMS"
  VendorName   "HP"
  VertRefresh  40-70
  # 1280x768 @ 60.00 Hz (GTF) hsync: 47.70 kHz; pclk: 80.14 MHz
  Modeline "1280x768_60"  80.14  1280 1344 1480 1680  768 769 772 795  -HSync +Vsync
EndSection

I don't know what, if anything, Xorg will see and configure with your TV connected and on.

[pfnuesel]

Thanks for all your help. I now have the xorg.conf file, but I still don't know how to drive the VGA port. I was expecting to see something when doing xrandr, but no. Might play around with it later but my motivation with this tool is going to zero.

[stevea]

Your converter says ....

Delivers a clear, sharp transmission – supports up to 1280 x 1024 and 1080p resolution and video amplifier bandwidth up to 1.65 Gbps / 165 MHz

So I think 1280x1024 is as far as you can set the VGA. xrandr does allow you to set the output ...
Use 'xrandr' to see the displays and supported modes then something like
xrandr --output VGA --mode 1280x1024

[pfnuesel]

Thanks also to you, stevea. It's really nice to see so many people willing to help.

I tried every possible setting with xrandr, I just don't get a signal on the TV. Tried it with Windows then and I was able to get a picture (but with wrong colors). But would be nice to have it running under Fedora.

Will try it later again, no access to TV right now.

[hieronymous]

Hi pfnuesel

Originally Posted by pfnuesel

When I go to Displays, I see an unknown display. Good thing is, that the TV changes the channel automatically to HDMI when I do that, so it seems to get a signal. However, I can only choose 1024x768 and 800x600 as a resolution for the TV. The TV itself is named as "unknown". Whatever I choose, I don't see anything on the TV.

When your tv changes channel to hdmi, have you explored the tv setup options (for hdmi) at that time?

If getting your PC displayed on your tv by any means is the most important, have you got a vga-to-vga cable you can try?

[pfnuesel]

Originally Posted by hieronymous

When your tv changes channel to hdmi, have you explored the tv setup options (for hdmi) at that time?

Yes, I did, but couldn't find anything helpful. There aren't many options to choose from on the TV and certainly I cannot choose a resolution.

Originally Posted by hieronymous

If getting your PC displayed on your tv by any means is the most important, have you got a vga-to-vga cable you can try?

The TV has no VGA input. It only has HDMI, Cinch and S-Video. Maybe S-Video would have been the better choice, as it is analog like VGA, but when it said easy connectable and such, I didn't think of it could be a problem.

[pfnuesel]

Hey guys!

It is working!!!

Thank you so much.

With xrandr and 640x480 it worked in the end. Higher resolutions do not work, I don't know why (both the TV and the converter should support higher resolutions) but I am happy as it is.

Thanks again!

[pfnuesel]

Before I mark this thread as solved, one last question:

If I type xrandr I have a list of resolutions and frequencys. When I plug in the converter, I have a very limited list of options. Is it possible to extend this list by hand?