Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: Kikus on February 28, 2014, 09:21:22 PM

Title: Nothing appears
Post by: Kikus on February 28, 2014, 09:21:22 PM
Hello,

I just received the card A20-OLinuXino-MICRO 4GB with android SD card
I connected to my computer screen and there is nothing that appears.
I tried the TV in HDMI, nothing.
VGA still nothing
How can I do?

Thanks for your answer

PS: Ya t'il un francophone dans le forum?
Title: Re: Nothing appears
Post by: progmetalbg on March 01, 2014, 08:49:02 AM
Hello,

What power supply do you use?
Are the red and the green LEDs close to the power connector switched on?
USB Serial cable like this one https://www.olimex.com/Products/Components/Cables/USB-Serial-Cable/USB-Serial-Cable-F/ (https://www.olimex.com/Products/Components/Cables/USB-Serial-Cable/USB-Serial-Cable-F/) is quite useful for troubleshooting boot issues.
Title: Re: Nothing appears
Post by: dave-at-axon on March 01, 2014, 09:11:31 AM
Also, how long did you wait?

I have found that the A20 does not show any boot images on the HDMI output and nothing is output until the desktop appears.
Title: Re: Nothing appears
Post by: Kikus on March 01, 2014, 01:09:42 PM
Hello

For power supply I use the https://www.olimex.com/Products/Power/SY0612E/.
When the power switched on only the red ligh is on.

I have waited 5 minuts  :'(
Title: Re: Nothing appears
Post by: resources on March 01, 2014, 04:42:46 PM
Do I get it right... you have a A20-board with 4GB NAND FLASH memory, but you want to boot from your SD-Card?

Push the RESET-Button and wait a couple of minutes. In case of it still does not work, reupload the image. (Click (https://www.olimex.com/wiki/A20-OLinuXino-MICRO))
Title: Re: Nothing appears
Post by: Kikus on March 01, 2014, 05:10:19 PM
I make this instruction "How do I write the official Android image to a micro SD card for my A20 board?"
on https://www.olimex.com/wiki/A20-OLinuXino-MICRO

and nothing...
Title: Re: Nothing appears
Post by: dave-at-axon on March 01, 2014, 06:30:50 PM
If you don't have it already, get yourself the USB-Serial cable for the board and connect to the UART0 connector. It will let you see what is happening at boot.

Another idea if you don't have the cable is to see if the same USB you used to flash the image to the board gets detected during the Android boot cycle. Does Windows (I assume you are using Windows but if not, use dmesg on Linux) and see if the Android debug connection appears in device manager (WIndows) or in the output from dmesg (Linux)

Make sure you have ADB installed. If you have Android Studio or Eclipse for Android development then this should be the case.

Type in "adb devices" from a command line or terminal and it should report if the device is present. If it does, this means that Android has booted far enough that ADB has started. This means the board is getting started so now type in "adb logcat" and you should start to see debug output from the board. You might want to re-direct this to a file so you can read it later. :)

Title: Re: Nothing appears
Post by: resources on March 01, 2014, 07:05:47 PM
Why do you try to boot from SD-Card, if you have nand flash memory on your board?! Check 5.2 How to download new Android image to the NAND memory of my A20 board? and remove your sd-card.
Title: Re: Nothing appears
Post by: Kikus on March 01, 2014, 08:24:05 PM
nand driver init failled !!!! :( :( :(
Title: Re: Nothing appears
Post by: resources on March 01, 2014, 11:57:17 PM
I had exactly the same error with both of my A20 boards. That's what I did to make it work:

1. I downloaded and extracted the image again.
2. I switched to another computer.
3. I didn't use an usb extension cable anymore and plugged it in directly now.

I don't know which of the point caused and solved the problem, but at least it's working now.
Title: Re: Nothing appears
Post by: Kikus on March 02, 2014, 08:30:44 AM
I have reloaded the the image
The uprgrade works, but i have already black screen....
2 days on that !!!
Title: Re: Nothing appears
Post by: resources on March 03, 2014, 06:37:18 AM
Mmh... it's hard to locate the problem from here. Are you sure it's not your HDMI-cable nor screen? Try another cable and another screen, if it's possible. I had to press the "Recovery"-button once to get it started. Otherwise I'm out of ideas for the moment. Maybe it's really a hardware problem.
Title: Re: Nothing appears
Post by: Kikus on March 03, 2014, 08:13:38 AM
Thanks very much All. ;) You are Great
The ardware return to Olimex.
Title: Re: Nothing appears
Post by: resources on March 03, 2014, 08:52:17 AM
Btw... I meant the RESET-Button all the time, not the Recovery-button. GL.
Title: Re: Nothing appears
Post by: olimex on March 25, 2014, 02:28:15 PM
we received back the board of Kikus and it works fine and pass all tests
I guess he didn't manage to make correctly the SD-card and this is why it was not booting