Hardware Reference
In-Depth Information
GPS module with data logging built in (see
Figure 3-13
). It
receives signals from satellites to determine its position on the
globe, then transmits this data to FLORA over a serial connec-
tion. The pads are all in a convenient order to match up exactly
with the FLORA main board. To make a wearable that helps you
navigate to a specific destination, combine the FLORA GPS
module with the compass module (
“FLORA Accelerometer/
Compass/Gyro (Motion Sensor)” on page 29
), which can sense
which way you're facing.
Figure 3-13.
FLORA Ultimate GPS module
This module, based on the MTK3339 chipset, is easy to use but
extremely powerful. Its -165 dBm sensitivity means it can pick
up satellite signals clearly, and it can update its location 10
times per second (10 Hz) using up to 22 satellites at once. It
draws only 20 mA of current and can be turned into an atomic-
precision clock by adding a coin cell backup battery. There is an
onboard antenna and also a u.FL connector for attaching an
external antenna. The red status LED indicates when the GPS
has a fix.
The GPS module uses serial to communicate to FLORA (TX/RX
pins) instead of I2C, unlike the other sensors mentioned in this
chapter.
Dimensions
: 30.5 mm/1.2
″
diameter × 5.98 mm/0.24
″
thick
