eDP-to-CH7511 problem on WEC7

[JKiss1]

Hi,

I want to use dual-channel 24-bit LVDS with Atom D2550 + Chrontel CH7511 on WEC7.

I have tried every possible settings in EMGD Configuration Editor, but CH7511's LVDS signals did not change and did not work.

CRT, DVI and internal LVDS ports are working correctly, but eDP-CH7511 not.

GPIO switch of CH7511 setting is OK.

When I tried this on DOS (eDP configured by BIOS) the CH7511 worked correctly, dual-channel 24-bit LVDS was correct, picture was correct on TFT.

When operating system don't modify the BIOS configuraton, the CH7511 will work well, but I think WEC7 modify it.

Could anyone help in this question?

Hardware: Advansus ICDT-IB2 Intel® Atom D2550 Mini-ITX Motherboard

OS: Windows Embedded Compact 7

Driver : Intel® Embedded Media and Graphics Driver v1.15.1 for Intel® Atom™ Processor N2000 and D2000 Series

[Kirk_B_Intel]

There is no specific support in the driver for CH7511. It is supposed to look like either a standard eDP or DP device and do signal and timing adjustments to LVDS invisibly to the system and driver. One thing to keep in mind is that the Ch7511 only converts from eDp/DP to LVDS what is fed it. So if your LVDS panel is 1024 x 768 and the driver outputs 1024 x 768 then it works. If the driver somehow outputs 640 x 480, or 800 x 600, then that is what will be converted to LVDS and sent to the LVDS panel which is unlikely to be able to display that.

So it is critical that you specify in your configuration:

-The EXACT resolution needed in a DTD OR be sure the driver only uses the EDID from the CH7511 set for your panel,

-AND set "fixed timing"

-AND disable "standard timing"

-AND set the correct resolutuion in WEC

-and likely set in the attribute the "eDP on DP" option (makes the driver do all the power management stuff that eDP requires and most DP to LVDS converts need us to do).

This should all help to make the CH7511 work properly. My guess is that somehow the driver is convinced to do a non-native resolution and that is whyt he panel does not work. Keep in mind that a DP monitor handles more resoltuons than just the native resolution (640 x 480 and 800 x 600 are assumes supported per PC specifications and MIcrosoft requirements).

The only other thing we can suggest is to contact Chrontel support as they are able to figure out what might be tripping up their chipsets and if there is a driver issue, they will work with us to correct it.

Hope this helps.

[wimpzilla]

Hello,

Sorry for necrothreading this discussion, but i have somehow the same issue, i think, with an old All-in-one Asus computer and windows 10.

I got my hand on 2 old Asus ET2012EUKS All-in-one computers, they are still running windows 7 fine along with a pentium g630, 4GB of ram and an old HDD.
This model does not have a discrete gpu, the pcb board indeed have the solder pad but they are not populated.

I decided that these could still be pretty useful hang to a wall, the model i got have no touch but there is the connector on the motherboard.
So i decided to check how windows 10 would/could run on these before treating them with cheap SSD.

Long story short, i could not get a picture working on windows 10 upon the installation of the Intel graphic driver, black screen with backlight on, HDMI output working, but nothing on the main monitor.

Until i install the Intel driver, i still got a picture, the generic Microsoft display adapter do the job managing to get a picture output, even if flickery.
I checked with blur busters page, it output 1600*900@64hz and everything run fine with basic display acceleration.

Now i dug a bit further, looked at the panel and sure it is a LVDS panel, so the hardware configuration should resemble to what found in old laptops of the same generations.
I checked on the pcb, and i found the same CH7511 eDP to LVDL converter chip handling the display output and the issue i got resemble a lot to what described here.

Unfortunately i'm not familiar with the display driver boot sequence on windows 7 and 10, but how i could get the same basic boot resolution that windows 7 use on 10, to not have the chip freak out?
Am i even in the good direction to solve this issue?

Thank you.

[CarlosAM_INTEL]

Hello, @wimpzilla:

Thank you for contacting Intel Embedded Community.

You should address your consultations related to the third-party devices listed in your previous message  as a reference to the channel mentioned on the following websites:

https://www.asus.com/support/Product/ContactUs/Services/questionform/?lang=en

https://www.asus.com/All-in-One-PCs/ET2012EUKS/HelpDesk/

Best regards,

@CarlosAM_INTEL.

[wimpzilla]

Hello

Thank you for the reply.
I will report to Asus but not sure they care much, i thought it would have been wiser to leave a message here in case someone need it.

Greetings.

[CarlosAM_INTEL]

Hello, @wimpzilla:

Thanks for your reply.

We would like to help you, but the proper information for the devices related to this situation is handled only by their manufacturer.

Best regards,

@CarlosAM_INTEL.

[wimpzilla]

Hello,

After some troubleshooting work that included modding the bios, installing manually a lot of Intel HD Graphics packages from the Microsoft Update Catalogue, i finally found out where the issue lies.

The Pentium g630 run a slightly modified version of the 2nd gen Intel iGPU, compared to what's found in Sandy Bridge processors like the i5-2400.

On Windows 10, when the driver installation occurs, it seems that the OS chooses to install the driver version related to the i5-2400 and not the one related to the pentium g630 iGPU.

I got it working on Windows 10 by choosing to install manually the Intel HD Graphics Family drivers instead of the usual Intel HD Graphic drivers.
When i installed the Intel HD Graphics Family version, the All-in-one screen finally popped into life, displaying the image correctly, with the same driver version that was giving me a black screen previously.

I don't know, maybe Windows 10 does not read correctly the hardware ids or cannot differentiate between the two version of the 2nd gen Intel iGPU like Windows 7 do?

Again, sorry for necrothreading this discussion, but it was pretty uselful to my troubleshooting.
Hope this can help Intel or anyone else experiencing the same issue on old hardware.
Pretty happy, everything works fine now.

Greetings, Wimpzilla.