Operation Manual

available at consumer electronics shops, or can be purchased even cheaper at online retailers such as Amazon.
Connecting a Keyboard and Mouse
Now that you’ve got your Raspberry Pi’s output devices sorted, it’s time to think about input. As a bare minimum, you’re going
to need a keyboard, and for the majority of users, a mouse or trackball is a necessity too.
First, some bad news: if you’ve got a keyboard and mouse with a PS/2 connector—a round plug with a horseshoe-shaped array
of pins—then you’re going to have to go out and buy a replacement. The old PS/2 connection has been superseded, and the Pi
expects your peripherals to be connected over the Universal Serial Bus (USB) port.
Depending on whether you purchased the Model A or Model B, you’ll have either one or two USB ports available on the right
side of the Pi (see Figure 1-4). If you’re using Model B, you can connect the keyboard and mouse directly to these ports. If
you’re using Model A, you’ll need to purchase a USB hub in order to connect two USB devices simultaneously.
Figure 1-4: Model B’s two USB ports
A USB hub is a good investment for any Pi user: even if you’ve got a Model B, you’ll use up both your available ports just
connecting your keyboard and mouse, leaving nothing free for additional devices such as an external optical drive, storage device
or joystick. Make sure you buy a powered USB hub: passive models are cheaper and smaller, but lack the ability to run current-
hungry devices like CD drives and external hard drives.
If you want to reduce the number of power sockets in use, connect the Raspberry Pi’s USB power lead to your powered USB hub. This way, the Pi
can draw its power directly from the hub, rather than needing its own dedicated power socket and mains adapter. This will only work on hubs with a
power supply capable of providing 700mA to the Pi’s USB port, along with whatever power is required by other peripherals.
Connecting the keyboard and mouse is as simple as plugging them in to the USB ports, either directly in the case of a Model B
or via a USB hub in the case of a Model A.
A Note on Storage
As you’ve probably noticed, the Raspberry Pi doesn’t have a traditional hard drive. Instead it uses a Secure Digital (SD) memory card, a solid-state storage
system typically used in digital cameras. Almost any SD card will work with the Raspberry Pi, but because it holds the entire operating system, it is
necessary for the card to be at least 2 GB in capacity to store all the required files.
SD cards with the operating system preloaded are available from the official Raspberry Pi Store along with numerous other sites on the Internet. If you’ve