board, the variable resistor for the
LCD contrast control occupies the
space of the missing pins.)
Before we get into the details of
the RazzPi-LCD circuit, let’s take a
quick look at how the board is
connected to the Pi, to a breadboard,
When I first designed the RazzPi-LCD, I decided to use the
Adafruit.com “Pi Shell” case. This
particular case works perfectly for the
RazzPi-LCD because it includes a
GPIO header opening that extends a
little around the side of the case. In
order to see what I mean, refer to
Figure 3 which shows how the GPIO
opening wraps around on the Pi Shell
case. Figure 4 is a side
view of my Pi installed in
the Shell case, with a
inserted onto the Pi’s
GPIO header. As you can
see, the top of the RazzPi-LCD is directly in line with
the top of the case. This is
necessary so that the
breadboard can sit flat on
top of the enclosure.
Figure 5 is a photo of
the bottom of a breadboard that’s
been slightly modified to make sure
that it does sit flat on the top of the
case. As you can see, I removed a
small section of the foam backing
and covered the exposed power rails
with electrical tape. When the
breadboard is right side up (with the
modification in its upper left corner),
the modified area will sit directly on
top of the short ends of the 2x13 pin
SHARPENING YOUR TOOLS OF CREATIVITY
November 2014 13
■ FIGURE 1. RazzPi-LCD, top view.
■ FIGURE 2. RazzPi-LCD, bottom view.
■ FIGURE 3. Adafruit "Pi Shell" case.
■ FIGURE 4. RazzPi-LCD and case, side view.
■ FIGURE 5. Breadboard, bottom view.