User manual

4D SYSTEMS Armadillo-43(T) – Linux based Computer Display Module
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Armadillo-43(T) – Linux based Computer Display Module
kgdboc=ttyAMA0,115200 console=tty1
Save the file, overwriting the existing one.
Navigate and edit /etc/inittab using the same
method above
sudo leafpad /etc/inittab
Comment out the bottom line by putting a '#'
symbol at the start of it, where the bottom line is:
T0:23:respawn:/sbin/getty -L ttyAMA0
115200 vt100
Save the file, overwriting the existing one.
Reboot the Armadillo.
When rebooted, the Armadillo will have its Serial
UART available for the User.
Control the LCD Backlight 6.4.
In order to control the backlight on the Armadillo,
the backlight driver needs to be enabled, which is
enabled by default on the 4D Systems Raspbian
image.
The backlight can be controlled from the terminal,
or from a bash script. The following command can
be used to set the backlight from 0 to 100%.
echo 80 > /sys/class/backlight/gpio-
backlight.0/brightness
The above will set the backlight to 80%. Simply
change the ‘echo 80’ to be anything from 0 to 100.
Calibrating the Touch Screen 6.5.
The touch screen on the Armadillo is controlled
using a Microchip AR1021 Resistive Touch
Controller, which is interfaced to the BCM2835
using I2C. This controller is connected to the I2C0
channel of the BCM2835.
Calibration is easiest launched using the Armadillo
Config tool, which can be found in the ‘start’ menu
of the 4D Systems Raspbian OS, or can be
launched via Terminal by typing:
sudo armadillo-config
Simply click on the icon titled ‘Touch Calibration’
and follow the on screen prompts.
Rotating the Display Orientation 6.6.
It is possible to rotate the display in order to
satisfy various mounting configurations, such as
Portrait, Landscape, Reverse Portrait and Reverse
Landscape.
This is very simple to do by using the Armadillo-
config tool, which can be found in the ‘start’ menu
of the Raspbian OS, or can be launched via
Terminal by typing:
sudo armadillo-config
Simply click on the Rotate Screen Option, and
select the orientation of your choice.
Once this has been selected, click Save, and Exit
the tool. You will need to restart the Armadillo for
the changes to take effect.
The User Button 6.7.
On the back of the Armadillo is a tactile push
button labelled User. This button can be
configured by the User to perform a set action, or
multiple actions, dictated by a bash script which is
executed when the button is pressed.
By default, the button is set to execute a script
called ‘Killthem’, which simply searches for specific
processes running and kills them if they are
running. This is used to kill applications which do
not have touchscreen control and typically require
a keyboard, so the application can be exited
without the need for a keyboard to be connected
to the Armadillo. This script can be edited to suit,
or can be replaced entirely with a different script
for a different purpose, such as safely shutting
down the Armadillo for example.
The User Button is connected to a GPIO on the
BCM2835 SoC, and therefore if the GPIO is to be
used for another purpose, then the User Button
can no longer be used.