Hardware Reference
In-Depth Information
Raspberry Pi does diferent tasks, the amount of power it needs varies. Consequently, with
some adapters, it may work some of the time, but then stop when it needs more power. Your
power supply should provide a minimum of 700mA at 5V or at least 3.5W. Most power sup-
plies will have a label that details the output power or current it can provide. However, some
power supplies don't deliver what they claim! If your Raspberry Pi partly works and suddenly
stops working, particularly when you ask it to do something more intensive such as graphics,
then the power supply is probably not up for the job. In some cases it is not the power supply
itself that is at fault, but the cable connecting it to the Raspberry Pi. Some cables can have a
relatively high resistance and so can drop the voltage getting to the computer.
he power adapter also has to supply any peripherals plugged into the Raspberry Pi. If a
peripheral takes too much power, then your Raspberry Pi will stop working. If you know how
to use a multimeter, you can check the voltage supplied by the power supply under load. You
can ind information about how to do this in the
Raspberry Pi User Guide
(Wiley, 2012). If you
measure less than 4.3V at the test points, then it might be worth changing the cable before
you change the power supply. Or you can try using a diferent adapter.
If You Need More Help
If you're still struggling with your Raspberry Pi, then you may need other sources of assis-
tance. A major beneit of the huge popularity of the Raspberry Pi is the support ofered from
an enthusiastic, helpful community. See if you can ind a solution at
http://elinux.
You can often get help in person by attending a user group or local meeting, commonly
referred to as a
Raspberry Jam.
It's a worldwide network, so just check
http://raspberry
jam.org.uk
to ind the nearest location.
he
Raspberry Pi User Guide
also provides suggestions for troubleshooting and conigurations
to work with speciic hardware.
Let the Fun Begin!
Now that you've got your Raspberry Pi powered up, it's time to start having fun with the
projects. he Insult Generator project in Chapter 2 is a good one to start with because it
introduces how to program the Raspberry Pi in Python - and more importantly, it can be
used to insult your friends and family!
