Hi
At the beginning I would like to say hi. I do not know English well, so please be patient.
I will try to describe my problem.

I have a Nanopi K2 and a Waveshare 7 LCD HDMI (C) display. After connecting and starting Nanopi, nothing is displayed. It seems to me that the computer can not properly start. When I turn on the Nanopi and the system will load, then I connect the display and it works correctly. Picture and touch work.

What could be the reason? Where to start?

Regards
Trebor

Edited June 27, 20188 yr by trebor

can you send the output of 'sudo armbianmonitor -u' in both scenarios? may get others some hints. 

The system is running with a connected display. He works properly. After sending the command in the terminal:

"sudo armbianmonitor -u"

I get the result:
http://ix.io/1f7l

This is the correct entry for Raspbian (config.txt):

max_usb_current = 1
hdmi_group = 2
hdmi_mode = 87
hdmi_cvt 1024 600 60 6 0 0 0
hdmi_drive = 1

Where do I have to put it in Armbian?

Where are the drivers located? What is responsible for the correct detection of the display during system startup? What is the correct entry for Xorg?

What display is compatible with Nanopi K2? Connected to GPIO or HDMI. Maximum size 7inch.

Please, some tips.

1 hour ago, trebor said:

What display is compatible with Nanopi K2

You need to ask FriendlyArm/WaveShare if they have any. We can merge drivers to the kernel if you come up with a working patch. That's all we can officially do on this subject. Armbian is ready to build out of the kernel tree drivers ... if you have sources and support from Waveshare. For SPI based displays ... it could work.

Thank you Igor. I do not understand why the image appears only after the system is fully loaded. Then I can connect the display and use it. I think I can start the display right now. I do not know how to force the system to detect it when the system boots up. Please, give me some tips. Thank you again for your help. I apologize for my poor English.

There is a difference between having the display working in a kernel and having it also working in early boot of u-boot.

To have the display initialized early in u-boot, you need to have driver and configs included in u-boot itself and have this custom u-boot built specifically for your setup.

 

Thank you for the information, Martin Ayotte. In that case, can I extract the driver from the kernel and implement it to u-boot? Is it possible?

Probably, but it will be a tedious task.

Better doing searches for which driver is already included and find compatible screen according to search result.

 

 

 

Please, for directions what I must do. How to start? Thank you.

I don't know if this could help, but I did a googling of "NanoPi K2 u-boot lcd support", it found a fork of u-boot here : https://github.com/nickfox-taterli/amlogic-nanopi-k2-uboot

And a part of the README shows :

 

 

- LCD Support: CONFIG_LCD Define this to enable LCD support (for output to LCD display); also select one of the supported displays by defining one of these: CONFIG_ATMEL_LCD: HITACHI TX09D70VM1CCA, 3.5", 240x320. CONFIG_NEC_NL6448AC33: NEC NL6448AC33-18. Active, color, single scan. CONFIG_NEC_NL6448BC20 NEC NL6448BC20-08. 6.5", 640x480. Active, color, single scan. CONFIG_NEC_NL6448BC33_54 NEC NL6448BC33-54. 10.4", 640x480. Active, color, single scan. CONFIG_SHARP_16x9 Sharp 320x240. Active, color, single scan. It isn't 16x9, and I am not sure what it is. CONFIG_SHARP_LQ64D341 Sharp LQ64D341 display, 640x480. Active, color, single scan. CONFIG_HLD1045 HLD1045 display, 640x480. Active, color, single scan. CONFIG_OPTREX_BW Optrex CBL50840-2 NF-FW 99 22 M5 or Hitachi LMG6912RPFC-00T or Hitachi SP14Q002 320x240. Black & white.
 

 

 

EDIT : BTW, the same part of README is also there in U-Boot Mainline : http://git.denx.de/?p=u-boot.git;a=blob;f=README;h=b1ddf89fc588290a85311c713260df3718e1c86e;hb=HEAD

 

Thank you for your help. It will take a lot of time. But I'm not giving up yet.