Troublemaker (hibernating again after RoboGames, but
hopefully not for 13 years this time) watching over the
proceedings. We find it to be quite a relaxing experience
actually — inserting the stackable headers in the board
means that it can stand steady as you dot your iron along
the underside of the board, not unlike
MacReady dipping the hot wire into various
blood samples in an attempt to identify “The
Thing.” The soldering is so straightforward that
it would make an excellent introduction to the
skill for newcomers to the electronic craft.
The SparkFun website contains a very useful
online Hookup Guide for the Wi-Fi shield, which
is not as risqué as it sounds. The Hookup Guide
walks through the entire process of setting up
and using the shield, and even links to a tutorial
on soldering for the newcomers.
The Hookup Guide also gives a nice
overview of the shield hardware, with bright
high-res close-ups of the board and its pinouts.
One of the interesting parts of the board
hardware is the serial switch which allows you to
choose whether the RX and TX signals go to the
Arduino’s hardware ports (pins 0 and 1) or serial
port (pins 8 and 9).
The Guide recommends leaving the
switch in its default position of selecting the
software serial. If you switch to the
hardware serial, all the programming will
also go to the ESP2866, which the Guide
cryptically cautions could send the ESP2866
into an unknown (though recoverable) state.
Just like shrinking hapless kids with a
shrink ray, just because you can recover their
normal state doesn’t mean the initial
digression is a good idea. So, we resolved to
stick with the software serial. Sticking with
the software serial also meant that we could
stick with the default baud rate of 9600.
Other hardware features include a reset
button (which resets the underlying Arduino
but not the Wi-Fi shield) and a helpful LED
status light that blinks when trying to
connect and stays solid with a successful
Upon becoming oriented to the
hardware, we were ready to stack the shield
onto our Uno. Our Uno has a USB-B
connector for programming which is a little
on the bulky side. To avoid any electrical
impropriety (the USB connector sat just
below the solder pads for the FTDI
breakout), we covered the top of the USB
connector with electrical tape. In any event,
the proximity of the USB connector to the
pads (even if they were occupied by some 90 degree male
headers, as suggested) should not be a problem because
the Hookup Guide strenuously makes the point that good
clearance between the Wi-Fi shield and the Uno is
necessary to avoid possible interference with the Wi-Fi
56 SERVO 08.2016
TOO CLOSE FOR COMFORT.
INTERNET CONNECTION SUCCESSFUL!
EXTRA ROOM FOR THE WI-FI ANTENNA.