If you have a phone charger with a micro B male connector, you may be in luck! Look on the plug end
and see if the volts and mA are listed. If your phone charger provides 5 volts 700mA, then you can
use it to power your Raspberry Pi. Some people have found that other chargers, such as those to
power ebook readers, work as well.
By the Way: The Longer Cable
When finding a cable for your Raspberry Pi, keep in mind that the longer the cable, the
more flexibility you will have. If you use a short cable to connect your Pi to power,
then you will have some limitations on where your Pi can move and be set down. In
general, longer cables equal greater flexibility.If you happen to live in a modern apartment or home and your wall sockets have USB A ports in them,
you can power your Raspberry Pi through those ports. You will need to purchase a cable with a USB
A male connector on one end and a micro B male connector on the other end. If you don’t already
have these wall sockets, you can have an electrician replace your regular wall sockets with A port
sockets or you can use adapters.
A Middle-of-the-Road Power Supplies
If you do not want to share a charger with your phone or ebook reader, you can buy your Raspberry Pi
its own power peripherals. In this case, you will need a USB power plug that plugs into a wall outlet
with a USB A port. Also, you will need a cable that has a USB A male connector on one end and a
USB micro B male connector on the other. Figure 1.3 shows an example of this.