Tinker Board Forum

Full Version: Boooting Android without display
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Hi,
As a review, and to avoid ppl having same issue as mine :
It took me a day to figure out that the Android version for Tinkerboard can not boot without proper hdmi display connected to it :

i tried two different display :

24" Asus vk246h monitor but it seems hdmi version is tool old and resolution or refresh is not good for the ThinkerBoard
&
Those little 5" hdmi 800*480 display from Ebay (waveshare) with the same problem

However on a modern 24" monitor samsung s24d340 it's booting smooth and running well. 

I'd like to make that 800*480 display working with TinkerBoard, but it seems the rockchip kernel is checking display resolutions somewhere at boot...
Do you know how can i achieve that ?

Thank you
Having the same issue here. Have tried 3 different displays without success. Also had problems with SDCards and RPi power supplies.. This device, even with the great specs, is doomed to failure if these issues continue. NO such issues with Raspberry Pi's........
Yes, it requires a strong power supply,

On european standard (230v -50 hz), all of my 5v -2 amp usb power supplies can't boot this device.

Actually i'm using a 12v -1.25 amp led power supply connected to 5v transformer to get the required watts.
I'm also using a class 10 micro sd card, i didn't try cheap sd card but it's certainly not a good solution here imho

also, the chipset rk3288  is mostly used in tv set-top-box that already have integrated power supplies or transformer on board...

On other rk3288 solutions, the chipset is mostly coupled with nand or emmc flash memories which are much faster but also more expensive.. but not adapted to "hobbyist" or low costs solutions


i'm going to try to build my first kernel soon to try to fix those resolutions problems
Hello guys,
i tried to get a 7" Display (800x480) with HDMI working on Tinker Board and it boots up correctly so no problem so far.

But there is one main problem i have, the HDMI resolution is only 720x480 so it does not support the full pixel width like the display would support and in this case the text of the app shortcuts shown on the main screen (Launcher) or in the menu is not sharp and looks blurred.

I tried to change dpi and resolution with the "adb shell wm" commands but it does not work, and in the case i change the resolution the Tinker Board is going to boot failure and i have to set up the latest Android version (13.11.0.5) again on the SD-Card.

Nothing worked so far, when i used a windows computer and connect it with the HDMI port the resolution of 800x480 is supported and works without any issues.
(09-26-2017, 10:56 AM)Locke Wrote: [ -> ]Hello guys,
i tried to get a 7" Display (800x480) with HDMI working on Tinker Board and it boots up correctly so no problem so far.

But there is one main problem i have, the HDMI resolution is only 720x480 so it does not support the full pixel width like the display would support and in this case the text of the app shortcuts shown on the main screen (Launcher) or in the menu is not sharp and looks blurred.

I tried to change dpi and resolution with the "adb shell wm" commands but it does not work, and in the case i change the resolution the Tinker Board is going to boot failure and i have to set up the latest Android version (13.11.0.5) again on the SD-Card.

Nothing worked so far, when i used a windows computer and connect it with the HDMI port the resolution of 800x480 is supported and works without any issues.

On playstore i found ''Easy DPI Changer" (requires root) to change resolution, but it doesn't work on my 5" display (it keeps 1920*1080 resolution)
can you show boot error message when this failure happens ? (via uart debug)
I also tried the app EASY DPI Changer but this is not really useful, you have to do it with the "adb shell wm" command than you can change resolution or dpi and this takes successfully effect but with the problem (must not be in every case but in my case) that the Tinker Board is booting up so that i am at the android Desktop and than fails.

i do not know how to debug via UART over the GPIO pins right?
(09-27-2017, 07:21 AM)Locke Wrote: [ -> ]I also tried the app EASY DPI Changer but this is not really useful, you have to do it with the "adb shell wm" command than you can change resolution or dpi and this takes successfully effect but with the problem (must not be in every case but in my case) that the Tinker Board is booting up so that i am at the android Desktop and than fails.

i do not know how to debug via UART over the GPIO pins right?

yes, there is one uart port dedicated for kernel messages debug by default : 

[Image: pic_gpio.png]
just connect a standard usb->rs232 converter to gpio 8 & 10 & gnd
and launch terminal on pc to receive messages kernel buffers
Hey thanks for the info.
I could fix my problem, i looked for a better or lets say more stable power supply and now i can change the resulotion with the command "wm size" also density is no problem.
But what i found out is that the Tinker Board is using on my display (7" with max 800x480) if you look which resolution it physikaly has right now (by only using the command "wm size" ) default 1920x1080 so the Tinker Board has to upscale it i think and so it looks blurred.
And the strange thing is when you look at the HDMI resolution in settings it says ( and it doesnt matter what you enter ore editing on resolution) 720*480.
I am now using the resolution 1444*960 and with this resolution it looks best.

It is really strange but works, in some cases i have to enter it again because it changes sometimes to default (1920*1080)