Hardware Manual

North Pole Engineering © North Pole Engineering Inc. 2020
221 N 1st St, Minneapolis, MN 55401
www.npe-inc.com
612.305.0440
GEM3NFC Overview
Overview
The following picture provides an overview of the various hardware elements of GEM3NFC
board.
Data, power, & I/O connector
The data, power, and I/O connector provides a means to connect a supply voltage of 3.3V to
the GEM3NFC module as well as UART TX and RX lines for serial communications between
the GEM3NFC module and the fitness equipment console MCU. The GEM3NFC UART lines
are TTL level and operate at 115.2Kbps.
NOTE: External connection to the UART TX and UART RX lines should be connected as
shown below. Connect host MCU TX to pin 10 (TX) on GEM3NFC module and host MCU RX
to pin 12 (RX) on GEM3NFC module.
The connector is JST BM14B-ZPDSS-TF(LF)(SN). The mating JST connector housing is JST
ZPDR-14V-S and is available through Digi-Key and other distributors.
Data, power, and I/O connections:
GEM3
Data, Power & I/O
NFC
Reader
NFC Tag Board Connector
NFC Antenna