1) First of all, I had modified the source.list for apt-get because of another information in thoses forums:
I modified all my lines like:
deb http://ports.ubuntu.com/ubuntu-ports/precise main universe
deb http://ports.ubuntu.com/ubuntu-ports/trusty main universe
This must not be done!!
Why? Because all upgrade was successfull and everything works great, until I install gdebi package (to install package graphically). Then my X windows sessions was a black screen. I tried many things and understood that LXDE was running but not displaying anything (I could use Ctrl+Alt+F1 to see it) and this is because gdebi package from trusty source is NOT compatible with the pcduino kernel provided (although upgraded to 14.04.5LTS), changes some X server configuration and ... X server gives a black screen. But gdebi is not the only one. I installed too pavucontrol after going on 14.04 and then... the same black screen. We obtain black screen with some updates of packages concernong X windows and then pcduino won't work any longer. Stay with 12.04.
So DON'T USE trusty first (you can install gdebi first with precise sources, pavucontrol, in Lubuntu 12.04 and then upgrade to trusty after, then no black screen occurs, but don't install anything else afeter going on 14.04 unless you have the risk of black screen). I burnt many times NAND and kernel and reinstalled everything and testes many things and that is my conclusion.
I had the ID keys mismatch only with trusty sources (Lubuntu 14.04), no problem with precise sources (Lubuntu 12.04)
2)Second thing: I found the problem, why there is a distribution conflict when using the lines added to sources.list:
deb http://ubuntu.pcduino.com/pcduino3/ pcduino main
deb-src http://ubuntu.pcduino.com/pcduino3/ pcduino main
the line "deb http://ubuntu.pcduino.com/pcduino3/ pcduino main" refers to the url:
The first part: "http://ubuntu.pcduino.com/pcduino3/"is the base url, then you have a space between this base url and pcduino, it means that you must have a subdir named "dists", then you have another space between pcduino and main, thos means that you access the subdir and file "main/source/Sources". This is the way source packages are meant to be built.
The file "Sources" lists all the files in the subdir "source" and their size and checksum.
So it gives you access to the files in the subdir "source".
But if you see what is at the target url ""http://ubuntu.pcduin...o/main/source/"
Sources 02-Dec-2016 15:07 1101
pcduino-dev_0.1-1.debian.tar.gz 02-Dec-2016 15:07 10K
pcduino-dev_0.1-1.dsc 02-Dec-2016 15:07 1723
pcduino-dev_0.1-1_source.changes 02-Dec-2016 15:07 2143
pcduino-dev_0.1.orig.tar.gz 02-Dec-2016 15:07 46K
And nothing of those files are the kernel files for pcduino3. So there is a problem.
But I could find the right files in another subdir:
Here we can list files:
Packages 02-Dec-2016 15:07 5671
pcduino-arduino-ide_0.1_armhf.deb 02-Dec-2016 15:07 10M
pcduino-arduino-ide_0.2_armhf.deb 02-Dec-2016 15:07 10M
pcduino-cloud9_0.1_armhf.deb 02-Dec-2016 15:07 33M
pcduino-config_0.1_armhf.deb 02-Dec-2016 15:07 9318
pcduino-config_0.2_armhf.deb 02-Dec-2016 15:07 11K
pcduino-dev_0.1_armhf.deb 02-Dec-2016 15:07 169K
pcduino-kernel_0.1_armhf.deb 02-Dec-2016 15:07 9M
pcduino-kernel_0.2_armhf.deb 02-Dec-2016 15:07 9M
pcduino-kernel_0.3_armhf.deb 02-Dec-2016 15:07 9M
pcduino-linux-headers-3.4.29+_0.1_armhf.deb 02-Dec-2016 15:07 7M
pcduino-linux-headers-3.4.79+_0.1_armhf.deb 02-Dec-2016 15:07 7M
pcduino-scratch_0.1_armhf.deb 02-Dec-2016 15:07 38M
pcduino-scratch_0.2_armhf.deb 02-Dec-2016 15:07 38M
pcduino-scratch_0.4_armhf.deb 02-Dec-2016 15:07 38M
pcduino-squeak_0.1_armhf.deb 02-Dec-2016 15:07 747K
pcduino-xbmc_0.1_armhf.deb 02-Dec-2016 15:07 29M
pcduino-xbmc_0.2_armhf.deb 02-Dec-2016 15:07 29M
pcduino-xbmc_0.3_armhf.deb 02-Dec-2016 15:07 29M
pcduino_0.1_armhf.deb 02-Dec-2016 15:07 782
pcduino_0.2_armhf.deb 02-Dec-2016 15:07 784
pcduino_0.3_armhf.deb 02-Dec-2016 15:07 756
We can see that the kernel files for pcduino3 is here: "pcduino-kernel_0.1_armhf.deb " and the headers sources for compiling kernel 3.4.79+ to compile your drivers is here too "pcduino-linux-headers-3.4.79+_0.1_armhf.deb".
So all is here. But we can't access it because it is at the wrong place.
So, if an admin here could replace the files at the correct place the firts post of this topic would be a suefull instruction since the apt-get sources would be right.
I can say that those files are the right ones, since I downloaded the headers for 3.4.79+ and could use them. So if no admin action is taken to repair the wrong file place, you can do it like me:
Use your Chromium web browser in Lubuntu 12 of your pcduino to download the package you want (for me the headers of the kernel):
(or use a wget command line instruction if you wish), and then install the package you just downloaded (I installed it in graphic mode with gdedi and double click on the .deb file) and then ... it works!
If you just want to laucnh command lines to do it with no search of what to do, I put here the instructions:
wget -4 http://ubuntu.pcduino.com/pcduino3/dists/pcduino/main/binary-armhf/pcduino-linux-headers-3.4.79%2B_0.1_armhf.deb
When download is finished, then install package:
sudo dpkg -i pcduino-linux-headers-3.4.79+_0.1_armhf.deb
This can solve the issue for all those like me who try to install 3.4.79+ headers for pcduino from wiimu sources no longer available.
If admin solve the wrong place files of source package, the procedure I wrote here will not be usefull.