Black screen after boot

Hi everybody,
sorry for my poor english (i’m french and don’t speak very well).
I’ve a problem with my khadas pro box.
In first, i’ve tested the different possibility of Rom (Librelec, dual boot,…) and it was ok to burn the emcc… (complicated but ok)
Finally I decided to come back to librelec Rom in a burning TF card… So i apply the method offer in this site but don’t work (er.
When I boot the box, I have a green screen in first, after that the logo VIM and after nothing (black screen)… I don’t know exactly what I made but for know I’m blocked.

When I plug the box to My PC (W10), he don’t recognise it.
Is my box bricked?
Please help me, thanks

Hi, fidoboulettes:
In your case, you can follow up below steps to upgrade a new ROM:

  • Erase the eMMC first
  • Upgrade with the new ROM, recommend to upgrade with Android ROM on eMMC installation.

One question:
You said you got a black screan after boot, does your monitor display nothing or display with a ‘VIM’ Logo?

try this Blank screen emmc flash

Hi everybody and thanks for your help.
I’ve trying to erase the Emmc --> just one question about that… How much time does I wait before release the “power and function” buttons after the press of “reset”?
When I do this, i saw what it happens in my monitor and I always have the green screen and Vim logo.

If I connect the box in a USB port (under Windows 10), nothing appear in USB burning tool software… I’ve trying different USB port

So, after that, I’ve trying the solution of ric96 under my linux OS (Ubuntu budgie) and with my CH340 USB serial TTL and I obtain that:

Is it possible to flash the Emcc under linux?

Best regards

My VIM is in the same case, My Pc don´t recongnice the vim.
Test Upgrade Via a Burnning TF Card.
It works in my VIM

Currently, there’s not Linux upgrade tools available yet, you can have a try with the SD card upgrade approach.

regarding the USB-C upgrade approach on Windows: 3 seconds is needed.

So I’ve tried 2 method to burn a TF card with the last (??) Rom: Vim_Marshmallow_Root_170121.

Before, I erased the card with SDformater. first, i’ve used the tool of khadas: Burn card maker tool and after win32diskimager but the both method don’t work for me… I don’t know what to do… maybe it’s me and don’t understand something…
So I repeat my question… how much time to wait for erasing the emmc before realising the “power and function” buttons after reset?


Sorry, I misunderstood at first, 15 seconds would be enough for the emmc erasing process complete. (New ROM will reboot if the erasing is completed)

It seems that you got with wrong way, to upgrade Android ROM with SD burning card, what you needed is just Burn Card Maker Tool only, the one win32diskimager is not needed. So just follow this instruction to upgrade Android ROM for your VIM.

To upgrade via TFcard the correct methos is “Burn Card Maker Tool” only, and enter into upgrade mode.
To do this “upgrade mode” you need a buttons secuence :
Long press Power key without release
Short press Reset key and release
Count 2-3 seconds and release the Power key to enter into upgrade mode.

Hi guys,
I’ve already made it… but don’t work for me… I’ve made a try with burning card by win32diskimager for this reason.

That I’ve saw, if I wait about ~10 min, it appears the beginning sequences of booting ubuntu (my ancient rom) and disapear right now… and appear again 10 min later… and again and again… It’s very strange.

@Cimmarron: You say long press the power button… how much time? ~15s before short press reset key (like Gouwa recommended?)


Just in this secuence,
Vin complety turn of.
I long press power button without release
I plug in the usb cable to 5v adapter, then the Vim is tuning on.
Short press Reset key
count 3 seconds
and finaly I relaased the power button.

after that, an android screen appears and upgrade. I tested with diferents images,
good luck

Vin complety turn of.
I long press power button and funcion button without release.
I plug in the usb cable to 5v adapter, then the Vim is tuning on.
In the screen there is a VIM logo, after 10 second more or less the vin logo disapears. Release the buttons, The Emcc is clear.

15 seconds is for EMMC erasing :wink:

And 3 seconds is enough for VIM to enter into upgrade mode.

Do you know how to use USB-to-TTL serial tools, if yes, things would be more easy, as you can also try Serial Mode of following approach:

How to boot into upgrade mode

I guess you didn’t got EMMC erased yet, as everything on EMMC will be wiped out after erasing, so your VIM can’t display anything on monitor then.

And you need make sure that you have crated the bootable SD card with the ROM image.

Good luck.

Hi everybody,
to sum up that I’ve made:

  • Prepare a new sd card (32gb/class 10) with the khadas tool.
    there is a printscreen of my card:

  • Flash the Emmc: Vin complety turn of, I long press power button and funcion button without release, I plug in the usb cable to 5v adapter and wait about 15s (on my monitor I see the green screen, after the logo VIM appears and disappear).

  • I turn of the box, plug my SDcard, turn on the box with power button pressed, wait during 3s (with power button pressed), release the button…

I wait a little bit but the bugdroid logo don’t appear…
What is wrong for me??
I’m a little bit discouraged


Vin off completely
Press and hold power button,
still holding power button, press the reset button for 1 second(release reset key after 1 second), wait three seconds and release power button. That should enter upgrade mode.

From Khadas docs…
Long press Power key without release
Short press Reset key and release
Count 2-3 seconds and release the Power key to enter into upgrade mode.
If everything goes fine, now your display/monitor should display like this:"

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I’ve already made this and nothing happen.

Hi Gouwa, I’ve try with my USB-to-TTL tools under Ubuntu but when I start the command “kermit”, My box isn’t detected…

BTW, I noticed that my VIM board did not always reliably entered upgrade mode. However holding the power button pressed and inserting the USB cable, then releasing the button after the device appears always did the trick.

It happens when you plug youre box to the pc or to the dc adapter?

You can check step by step following Setup Serial Debugging Tool
You need to take notice that both Rx and Tx are connected correctly .