Operation Manual

specialised male-to-female jumper leads.
The Slice of Pi also offers a small amount of protection for the Pi. The use of female headers means it’s harder to accidentally
short-circuit two pins, and the spacing of the headers—with the eight general-purpose pins brought to one header and the other
specialised pins brought to another—makes wiring mistakes less likely. More importantly, the Slice of Pi doesn’t provide direct
access to any of the pins labelled as Do Not Connect (see Chapter 12, “Hardware Hacking”), so there’s less risk of damaging
the Pi with a wrong connection.
Figure 13-2: Connecting the Slice of Pi to a breadboard
The connections for an XBee wireless interface could also prove useful if you are considering using the Pi in an embedded
computing project. When combined with a compatible transceiver—such as an XBee, RF-BEE or RN-XV module—it allows
for wireless access to the Pi’s UART serial port. Such access could be used to read sensor details from the Pi, take control of
the Pi’s software or even control a Pi-powered robot from a remote location.
Finally, the prototyping area provides an alternative to breadboards or stripboards for smaller circuit designs. If you are
considering developing a small add-on module for the Raspberry Pi, such as a sensor board for reading temperatures or
detecting moisture, the required components can be soldered directly to the Slice of Pi. Thanks to the low cost of the board, this
provides an easy way to create bespoke add-on modules for the Pi that are entirely self-contained, with no wiring required—just
connect the Slice of Pi to the Raspberry Pi’s GPIO port and the device is ready to go (see Figure 13-3).
The disadvantage of the Slice of Pi lies in its simplicity. Its compact size means that it is unsuitable for the creation of larger or
more complex prototypes, and while the header layout provides some protection against short circuits, there’s no protection
against the use of 5 V components that can damage the Pi’s 3.3 V logic circuits. The labelling is also different to that used to
typically describe the Raspberry Pi’s GPIO pins, which can lead to confusion when using a GPIO library not written with the
Slice of Pi in mind. Table 13-1 provides a translation from one labelling system to another.
Figure 13-3: The Slice of Pi, connected to the Pi’s GPIO port