Datasheet

Wiring to Arduino
Wire up
After soldering headers to the FONA module, plug it into a breadboard. We'll use an UNO, other Arduinos may be
different
Vio connects to 5V (or, with a 3V logic Arduino, 3V)
GND connects to GND
Key connects to GND (always on)
RX connects to digital 2
TX connects to digital 3 (9 on Leo/Micro, 10 on Mega)
RST connects to digital 4
We'll be using software serial to talk to the module. The Mega ('2560 based) can't use Digital 3 for FONA TX, so use
digital 10 instead. The Leonardo and Micro ('32u4 based) can't use digital 3 for FONA TX, so use digital 9 instead. See
this page (https://adafru.it/efC) for other pins you can use for FONA TX (SoftwareSerial Receive) on the Mega,
Leonardo, and Micro.
At this time we don't have support for Hardware Serial to talk to the FONA
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