AGX Stuck in low resolution Dual Monitor

I have a ConnectTech Rogue Carrier Board with an AGX Pro module and Jetpack 4.5.

The problem I am seeing is that Ubuntu is reporting that there are two “NVD 40” displays connected when there is actually only one 25" display. It also wont let me change the screen resolution to nothing about 720. It all worked before so this is a new problem.

See attached image.

Does “dual monitor” really matter here? If you use single monitor then it will let you choose the resolution?

hi @WayneWWW, No I dont need or want dual screen. There is only one screen attached which I want to be a higher resolution. I tried disabling the second screen within the settings menu which greyed it out but I still cant increase the resolution of the one display. Also, if I reboot the xavier, both screens are shown again.

Ok, so physically there is only one screen attached on the board.

Could you attach the screen, boot up and share the dmesg?

And just some guess about this issue. Our kernel driver has a hard-coded EDID which provides 720p resolution. When the board is not able to read the EDID from the monitor, no matter due to hardware or software problem, the driver will fallback and use this hardcoded EDID.

Under such situation, only 720p will be shown in userspace. Your dmesg will tell us if you hit this case or not.

The appearance of another monitor may due to the device tree from ConnectTech. Again, the dmesg will provide us clue.

That’s great thanks. Ill do that and report back. If the board cant read the EDID from the monitor as you predict, what would be the way of resolving this issue?

Since this is custom board, I can only suggest you firstly make sure the driver package you install to the board really matches ConnectTech’s board.

In brief, use the BSP provided from them.

low-res-displays-dmesg.txt (72.4 KB)
here is the DMESG output

As expected, there is problem reading the edid.

1.712289] tegradc 15210000.nvdisplay: hdmi: edid read failed
[ 1.712481] tegradc 15210000.nvdisplay: hdmi: using fallback edid
[ 1.712582] tegradc 15210000.nvdisplay: blank - powerdown
[ 1.715669] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.719752] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.723823] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.727903] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.731935] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.736059] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.740073] tegra-i2c 3190000.i2c: no acknowledge from address 0x50
[ 1.740613] tegradc 15220000.nvdisplay: hdmi: edid read failed
[ 1.740665] tegradc 15220000.nvdisplay: hdmi: using fallback edid

What kind of driver package does ConnectTech provide to flash the board? It does not look like a default setting from jetpack because you have 2 HDMI enabled.

They use this one

https://connecttech.com/resource-center/l4t-board-support-packages/

I’ve sent them the DMESG log too to see how this can be resolved