How to modify the jetson tx1 HDMI output resolution of 576i@50Hz?

Hi all:
I want to modify the jetson tx1 HDMI output resolution of 576i@50Hz,
and now i try to set tegra_dc_vga_mode to modify HDMI output.
Its output resolution also becomes 576i@50Hz, but the display is a black screen。

Can you give me some advice?

Thank you

You’d typically change via xrandr (“man xrandr”). If you want to see what your monitor thinks it can do, paste the content from the file you find with this in http://www.edidreader.com:

sudo find /sys -name edid

Hi linuxdev:
Thank you for your reply!
here is my edid;
0x00 0xFF 0xFF 0xFF 0xFF 0xFF 0xFF 0x00 0x05 0xE3 0x70 0x28 0x63 0x1E 0x00 0x00 0x0E 0x19 0x01 0x03 0x80 0x3E 0x22 0x78 0x2A 0xEE 0xD1 0xA5 0x55 0x48 0x9B 0x26 0x12 0x50 0x54 0xBF 0xEF 0x00 0xD1 0xC0 0xB3 0x00 0x95 0x00 0x81 0x80 0x81 0x40 0x81 0xC0 0x01 0x01 0x01 0x01 0x04 0x74 0x00 0x30 0xF2 0x70 0x5A 0x80 0xB0 0x58 0x8A 0x00 0x6D 0x55 0x21 0x00 0x00 0x1A 0x56 0x5E 0x00 0xA0 0xA0 0xA0 0x29 0x50 0x30 0x20 0x35 0x00 0x6D 0x55 0x21 0x00 0x00 0x1E 0x00 0x00 0x00 0xFD 0x00 0x17 0x50 0x1E 0x63 0x1E 0x00 0x0A 0x20 0x20 0x20 0x20 0x20 0x20 0x00 0x00 0x00 0xFC 0x00 0x55 0x32 0x38 0x37 0x30 0x0A 0x20 0x20 0x20 0x20 0x20 0x20 0x20 0x01 0x72 0x02 0x03 0x26 0xF1 0x4B 0x10 0x1F 0x05 0x14 0x04 0x13 0x03 0x12 0x02 0x11 0x01 0x23 0x09 0x07 0x07 0x83 0x01 0x00 0x00 0x6D 0x03 0x0C 0x00 0x10 0x00 0x38 0x3C 0x20 0x00 0x60 0x01 0x02 0x03 0x8C 0x0A 0xD0 0x8A 0x20 0xE0 0x2D 0x10 0x10 0x3E 0x96 0x00 0x6D 0x55 0x21 0x00 0x00 0x18 0x01 0x1D 0x00 0x72 0x51 0xD0 0x1E 0x20 0x6E 0x28 0x55 0x00 0x6D 0x55 0x21 0x00 0x00 0x1E 0x8C 0x0A 0xD0 0x90 0x20 0x40 0x31 0x20 0x0C 0x40 0x55 0x00 0x6D 0x55 0x21 0x00 0x00 0x18 0x4D 0x6C 0x80 0xA0 0x70 0x70 0x3E 0x80 0x30 0x20 0x3A 0x00 0x6D 0x55 0x21 0x00 0x00 0x1A 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0xA5

I found this description:
Detailed Timing Descriptor
Pixel Clock: 27MHz
Horizontal Active: 720
Horizontal Blanking: 144
Vertical Active: 576
Vertical Blanking: 49
Horizontal Sync Offset: 12
Horizontal Sync Pulse: 64
Vertical Sync Offset: 5
Vertical Sync Pulse: 5
Horizontal Display Size: 621
Vertical Display Size: 341
Horizontal Border: 0
Vertical Border: 0
Interlaced: false
Stereo Mode: 0
Sync Type: 3

2-Way Line-Interleaved Stereo: false
Is it support to display 576i@50Hz?

If you look closer at the right side listing in edidreader.com you’ll find you need to click on some parts of the “tree view” to expand and see them. Here’s one subset (no nice formatting like in the web URL):

X Resolution: 1920
X:Y Pixel Ratio: 16:9
Vertical Frequency: 60

X Resolution: 1680
X:Y Pixel Ratio: 16:10
Vertical Frequency: 60

X Resolution: 1440
X:Y Pixel Ratio: 16:10
Vertical Frequency: 60

X Resolution: 1280
X:Y Pixel Ratio: 5:4
Vertical Frequency: 60

X Resolution: 1280
X:Y Pixel Ratio: 4:3
Vertical Frequency: 60

X Resolution: 1280
X:Y Pixel Ratio: 16:9
Vertical Frequency: 60

In the above you have to use the X:Y pixel ratio (aspect) to compute what Y is. If your case is 576 horizontal, then you can use those directly to show 576 is not natively supported (sometimes resolutions are supported with not using the full screen…sort of a “best fit” basis).

Here’s another subset of the edidreader.com data:

Native: FALSE
VIC: 16
Format: 1920x1080p
Field Rate: 59.94Hz/60Hz
Picture AR: 16:9
Pixel AR: 1:1

Native: FALSE
VIC: 31
Format: 1920x1080p
Field Rate: 50Hz
Picture AR: 16:9
Pixel AR: 1:1

Native: FALSE
VIC: 5
Format: 1920x1080i
Field Rate: 59.94Hz/60Hz
Picture AR: 16:9
Pixel AR: 1:1

Native: FALSE
VIC: 20
Format: 1920x1080i
Field Rate: 50Hz
Picture AR: 16:9
Pixel AR: 1:1

Native: FALSE
VIC: 4
Format: 1280x720p
Field Rate: 59.94Hz/60Hz
Picture AR: 16:9
Pixel AR: 1:1

Native: FALSE
VIC: 19
Format: 1280x720p
Field Rate: 50Hz
Picture AR: 16:9
Pixel AR: 1:1

Native: FALSE
VIC: 3
Format: 720x480p
Field Rate: 59.94Hz/60Hz
Picture AR: 16:9
Pixel AR: 32:27

Native: FALSE
VIC: 18
Format: 720x576p
Field Rate: 50Hz
Picture AR: 16:9
Pixel AR: 64:45

Native: FALSE
VIC: 2
Format: 720x480p
Field Rate: 59.94Hz/60Hz
Picture AR: 4:3
Pixel AR: 8:9

Native: FALSE
VIC: 17
Format: 720x576p
Field Rate: 50Hz
Picture AR: 4:3
Pixel AR: 16:15

Native: FALSE
VIC: 1
Format: 640x480p
Field Rate: 59.94Hz/60Hz
Picture AR: 4:3
Pixel AR: 1:1

Among those non-native resolutions I see 576, but it is associated with horizontal, not vertical. If your 576i@50Hz is following the standard notation and 576 is for horizontal resolution, then it seems the monitor is reporting that it can’t do this. A video driver could do its own “editing” to rearrange a nearly compatible resolution to output in something the monitor actually responds to, but if xrandr sees valid data and still does not offer that mode, then no such support exists in the current mix of driver/graphics hardware/monitor.

Hi linuxdev:
Thanks for your reply, I said the 576i@50Hz format is actually 720x576i.
Field Rate: 50Hz
vmode:Interlaced.
Now I want to skip EDID detection, force HDMI output 576i.
what should I do?

The configuration files in “/etc/X11/” are where you would start. Before EDID existed there was no such thing as “hotplug” to configure monitors. Most monitors simply provided a number of “standard” resolutions, and those would work out of the box…but seldom were those resolutions the best the monitor could do…so in that case you’d either directly or indirectly edit the “/etc/X11/” files.

Indirectly meant a program could be used to select known monitors from a database (the driver disk shipped with the monitor), and the program would do the editing. Directly means getting out an editor and typing in the edits by hand. This latter is what you will have to do. If you have EDID, then the edits still take place, but they only take place in RAM and occur as a hotplug event doing the edits.

Take a look at the existing “/etc/X11/xorg.conf”. When Jetsons are first flashed this is a very minimal file because it expects everything else to be automatically filled in from the monitor’s EDID data upon plugin. You’re going to have a steep learning curve, as what you will need to do is learn about this file’s syntax. You will find there are “sections” which are interchangeable, and that one section may refer to another. Within this particular file consider that the JTX1 has two video output possibilities…one is the HDMI connector, the other is the eDP/DSI…the syntax of the file (regardless of whether it is in the file or from a hotplug EDID event) will typically be to disable the non-HDMI output and add content for the HDMI-related sections.

I think the “Device” you are interested in is the one which allows “AllowEmptyInitialConfiguration”…meaning the server will start even if no configuration is found…a case where the server will end up in some fallback standard mode (this is the set of standard modes from the original days of 15-pin D-sub VGA monitors). In your case the fallback mode is not what you want, so even if this mode works, you’d still have to add your own Monitor section describing the modelines (detailed timing descriptors…at edidreader.com see Descriptor 1 and Descriptor 2). Once you have your Monitor set you’ll probably bind this Monitor to a Screen or other layout section (I don’t know which sections, I have not edited one of these by hand in a very very long time).

Btw, modelines are simpler on digital panels; on analog they had a number of extra timings. You’ll still need to be able to create the modelines in the correct syntax (edidreader.com provides human formatting, you need to reverse this into a file edit). See:
https://en.wikipedia.org/wiki/XFree86_Modeline

There is also a program you can run on Linux called “cvt”. This is to calculate VESA modelines.

The xorg.conf man page is here:
https://www.x.org/archive/X11R7.7/doc/man/man5/xorg.conf.5.xhtml

One thing I suggest is to find what seems to be the simplest possible example of each section you might be interested in via a web search, and then find out how to modify it for your case. Test it and see if “/var/log/Xorg.0.log” produces an error on boot. If not, then you’ve progressed. Once you get your Monitor section associated with the display things should either work or be close to working.

Hi linuxdev,

I also tried to set the same interlaced resolution in xorg file. but all the interlaced modes are getting rejected by driver in Xorg.0.log file. does driver supports 576i mode?

regards,
Shivlal

No interlaced modes are supported…it is a guaranteed rejection.