Hardware Reference
In-Depth Information
Wiring the hardware with a proto cape
There are some special considerations when wiring this project as it is meant to go inside
an enclosure to provide the front panel. A stranded wire will bend and flex better compared
to a solid core. Once settled in the enclosure, we wouldn't expect the wires to strain or
move around, but they certainly will when you try to install the panel inside the enclosure!
We also have a few options to wire our project to BBB. We could use jumper wires with
male pins to insert into the female expansion headers, but these pins can come out easily,
especially when you put your project into the enclosure.
We'll use SparkFun's BeagleBone Black Proto Cape, DEV-12774, to easily combine our
circuit with BBB. This board breaks out power, ground, and other pin signals for expan-
sion. It includes an EEPROM, which is not only useful if you want to have persistent data
stored on your board but is also required if you are building a BeagleBone Cape, which
will be discussed in detail in the next chapter. The advantage of a protoboard, especially the
Beagle proto capes, is that we can solder male headers on the board and then use female
terminated wires, which tend to connect a little better. Plus, by using the male headers, we
can easily reuse the protoboard for a later project. However, these protoboards are not re-
quired, and if you are trying to save some money, with some creative wiring, you don't
need one.
If you are using the protoboard approach, you don't have to populate all the headers either.
Only the male pins that we need are soldered to the corresponding pads on the protoboard's
P9 header. The way these protoboards work is that each pin is duplicated on the pads next
to them. Solder the 100 Ohm resistor from P9_15 to the bottom of one of the male pins in
the middle of the board. Then, connect a wire from the male pin to the positive terminal of
the LED.
When complete, your project should look something like the following circuit diagram. We
don't have the control software running yet, but you can see the LCD displaying the band-
width usage. The following diagram doesn't have soldered connections to the potentiometer
for the ease of testing, but instead uses IC Hooks . In a finished installation, you will want to
solder the wires for a better mechanical and electrical connection.
Search WWH ::




Custom Search