included in the project files. If you are more comfortable
with Arduino rather than PIC systems, 4D Systems has
libraries and tutorials for interfacing their displays to
Arduinos. The Arduino IDE also has libraries for controlling
servos, so most of the complexity in my code can be
handled by the Arduino IDE. The comments in my source
code should help you in making the translation.
Construction
The 4D Systems displays require a microSD data card,
which stores the display information and any multimedia
files such as sound and pictures. The SD card must be
removed from the display and connected to your computer
whenever you make changes to the interface design.
When you install the display hardware into a case, you
need to be sure that you leave room to insert and remove
this card. Fortunately, the 4D IDE allows you to rotate the
display so you can properly position the memory card slot.
Figure 6 shows
the mostly bare
3D printed case.
The sunken
rectangle is sized
for the display,
which will be
held in place with a few dabs of rubber cement. The wire is
a servo extension cable, the male end of which is carefully
glued into the center of an opening in the case.
Figure 7 shows the outside view and the recessed pins
that will accommodate standard servo connectors. The
black mark helps orient the plug for proper polarity. The
recessed connector allows me to carry the box around
without fear of stabbing myself on the pins or breaking
them off as it rattles around in my tool case. In the photo,
you can also see the sliding bottom cover.
Referring back to Figure 4, you can see the electronics
are mounted on a half-sized prototyping board from
34 SERVO 12.2015
Figure 7.
Outside
of case.
Figure 6.
Bare
printed
case.
