Operation Manual

Chapter 13: Add-on Boards
Although you can to use the Raspberry Pi’s general-purpose input-output (GPIO) header directly, as you learned in Chapter
12, “Hardware Hacking”, a much better idea is to use a specialist prototyping board. Prototyping boards are add-on boards
designed to sit between your project and the Raspberry Pi, and range from the relatively simple—such as Ciseco’s Slice of Pi—
to the complex and powerful Gertboard.
At their most basic, add-on boards simply provide easier access to the Raspberry Pi’s GPIO pins. This may mean they can be
connected to a breadboard easier, or are spaced further apart and labelled to make connecting other devices simpler. Some
boards include circuitry to connect specific add-on devices, such as a small XBee wireless transceiver, and still others provide a
small surface onto which you can solder your own components to make a custom board.
The hardware market is constantly and rapidly changing, and the Raspberry Pi Foundation continues to encourage developers to
create more add-on devices. It would be impossible to create an exhaustive list of all the add-on boards available or planned for
release in the near future, but in this chapter, you’ll learn about three of the most common boards and how they can be used.
Ciseco Slice of Pi
The most basic of boards, Ciseco’s Slice of Pi (see Figure 13-1) is nevertheless useful. Supplied in kit form, Slice of Pi features
a small prototyping area, a space for an XBee wireless module and full access to the Raspberry Pi’s GPIO pins.
The compact Slice of Pi is designed to be connected directly to the GPIO headers on the top of the Raspberry Pi, with the rest
of the board covering part of the Pi’s surface—but not extending beyond the edges of the board nor obscuring any commonly
used ports. The Slice of Pi does, however, sit over the DSI video output connector. In most cases where this connector is used,
the ribbon cable can be routed underneath the Slice of Pi board without trouble.
Figure 13-1: The Ciseco Slice of Pi
The primary advantages over using the low-cost Slice of Pi rather than just connecting directly to the Pi’s GPIO header are the
labelling on the circuit board, which the GPIO header lacks, and the use of female headers. These allow you to use male-to-male
jumper leads or even just lengths of trimmed wire to connect the board to a breadboard (as shown in Figure 13-2) or other
circuit board—or even to connect components directly into the headers. The Pi’s male headers, in contrast, require the use of