I received the WBQUAD along with a case and a WiFi antenna. It runs off a 5V 2A power supply, which connects to it via a 5.5mm x 2.1mm center positive barrel connector. I imagine that it doesn’t use a micro USB connector because it has to draw 10 W of power, which is much more than the power provided by a standard USB connector.
I use Debian Linux. This is partly because it (and the APT package manager) is so familiar to me, partly because it always has seemed stable, partly because it’s based on a community rather than a product of a company, partly because it is the basis for many other Linux distributions, partly because the installation process gives me plenty of opportunity to choose how it is installed, and partly because upgrades between releases are fairly seamless.
Ordinarily, I use the Debian installer to install onto a desktop or laptop. For embedded computers (with their specialized hardware), the trend seems to be to download an image to an SD card. For the Pi, the Raspbian image is recommended by the Raspberry Pi Foundation. By contrast, wandboard.org offers only Ubuntu, Yocto, and Android images.
I did download their Ubuntu image, but, when I was validating it, I was confused because I didn’t see a Linux kernel; I learned subsequently that the image has the kernel in an unpartitioned section of the SD card – apparently, this makes upgrading the kernel a challenge.
Because I didn’t find Digi-Key’s support thread when I was looking for an OS image, I didn’t try out their Debian image. However, I did find a great thread on Google Groups with a link to Martin Wild’s Debian image for the WBQUAD. I am quoting the entry for the image here because hyper-linking to it is difficult if not impossible:
Martin Wild — Aug 6, 2013 6:47 AM
I’ve uploaded a new version of my debian image ,now with full Gnome, Owncloud, Aria2 with webinterface, Truecrypt with Gui (just launch with “truecrypt” inside Gnome-terminal), full setup ampache, Samba setup, new kernel wand 6.3 and some more tweaks
The Download size increased (naturally) but it still fits on a 4GB card. ip is fixed now via network manager (gnome) to 192.168.1.155, so change this if it doesnt fit your homenet. VNC is available but not running from boot. to vnc in open a terminal (ssh/putty)
and do “sudo vnc” to get a permanent running vnc session waiting for login until you logout again from gnome (pw=debian). to use aria2-downloader make sure the download-folder as defined in /etc/aria2/aria2.conf exists ,or aria will refuse to start.
The running webservices can be accessed by doing :
Owncloud —> /wbquad/owncloud
Ampache —> /wbquad/ampache
Aria2 —-> /wbquad/aria2
Webmin —-> https://wbquad:10000
Phpmyadmin —> /wbquad/phpmyadmin
(if your dns is not working correctly change wbquad to your ip-address 192.168.1.155/owncloud)
all passwords and usernames are stored inside /var/www/pass
Default login is debian:debian or root:debian
I proceeded to bring up my Wandboard as follows:
- download the four parts on a Linux box,
- concatenated them using
7z (i.e., 7-zip) to reconstruct the image,
dd to copy to an 8 GB micro SD card,
gparted to grow the second partition to fill the disk.
I ended up with an micro SD card with a 49 MB ext2 boot partition and a 7.8 GB ext4 root partition (and no swap partition, which wouldn’t make sense when using an SD card as a system disk). Next, I put it into the Wandboard, hooked the latter up to my HDMI TV, and powered it up.
I saw nothing on the screen. A few hours later, I read the quick-start guide in greater detail and learned that the WBQUAD has two micro SD card slots: one, intended for the OS, is on the daughter card along with the CPU and memory; the other, intended for removable storage, on the main card along with all the IO ports. I moved the micro SD card to the daughtercard and rebooted.
Now I could see HDMI output to the TV screen, but when I hooked the Wandboard to my DVI monitor, I didn’t get an image.
I am using a multisync monitor with DVI input and a native resolution of 1680×1050 @ 60 Hz. So, I needed to update /dev/fb.modes with an entry for this resolution/refresh combination. Here is what I added:
# D: 147.14 MHz, H: 66.22 kHz, V: 60.00 Hz
geometry 1680 1050 1680 1050 32
timings 6796 288 104 33 1 184 3
I used the following command to generate this:
gtf 1680 1050 60 -f -v
GTF is originally from Nvidia, but currently it is built into my image (it’s also in Raspian and may be standard Debian fare). I gather that it is from the XFree86 utilities. It is based on the VESA “general timing formula”. Since this hasn’t changed in a long while, neither has the program. I found the source code at Sourceforge, at Apple, and on archive.org. (I included three links because, when I tried this a few days ago, I got an error when trying to view it on sourceforge.)
I noticed the kernel boot parameters (for the first time) when reviewing the dmesg output, and noticed that the kernel command line included
On a hunch, I mounted /dev/mmcblk0p1 as /boot
and I edited /boot/uDev.txt, changing
Now I have full video with the resolution of my monitor and no flashing lines.
I was able to
ssh to it at the address assigned to it by DHCP. That means that I am not forced to use my TV as my display. I installed the Debian
tightvncserver package so that I can view a virtual desktop remotely. A sensible alternative would be to run an X server remotely, but I don’t have an X server installed on each and every machine that I might want to use to access my Wandboard.
The WiFi chip wasn’t working. Once again, Martin Wild has already provided a solution:
Martin Wild — Aug 15, 2013 6:37 AM
Posted in group: Wandboard
here is an recent (15.08.2013) hardwarepack using the 3.11 mainline kernel with audio and Wlan enabled. the required firmware files are already included
Just download to your wboard and do ./install
Now, I can see the WLAN interface with
ifconfig, so I am hopeful that I can get it running soon.
On a side note, one annoyance that I experienced with the gnome desktop was that, when I opened a terminal window, I could not use the up and down arrow keys to scroll through my command history because the up arrow was toggling the window maximization state and the down arrow was restoring a maximized window. The resolution was to alter the shortcut:
Applications > System Tools > System Settings
then Keyboard > Shortcuts > Windows
then change “Toggle maximization state” to Shift+Ctrl+Up
and change “Restore window” to Shift+Ctrl+Down
I found lots of “CANNOT SET SOC VOLTAGE BACK” lines in the output from dmesg. At https://groups.google.com/forum/#!forum/wandboard on 17 July 2013, Dave McMordie provided the solution:
edited /etc/rc.local to add a line
cpufreq-set -g performance
edited /etc/init.d/cpufrequtils to set the default governor to performance with the following lines: