Build the Reader Circuit

The reader circuit is made up of the RFM69 Feather M0, the NFC/RFID breakout board, a couple of 1.5K ohm resistors, battery power, and a Terminal Block Breakout FeatherWing for connections and its handy on/off switch.

The two resistors are necessary when connecting the PN532 board in I2C mode to the Feather

Below is an example of the circuit wiring as done on a breadboard for testing.

Here's the same circuit and wiring transferred to the Terminal Block FeatherWing, before and after attaching the Feather.

First, solder on the male header pins to the Feather as shown here. You can use the terminal breakout FeatherWing as a jig to keep things square.

Next, you'll use the prototyping area of the FeatherWing to add the two resistors in-line with 3V power and the SCL (serial clock) & SDA (serial data) pins.

Clip off the excess leads from the SCL and SDA ends of the resistors, but leave the other ends long for now so they can be connected to the 3V wires in a moment.

Now, run some hookup wire from the free ends of the resistors to the 3V rail.

Note how the 3V wires will connect to the resistors.

Wrap the free resistor leads to the wire ends, then solder in place.

Solder the UFL antenna connector to the underside of the Feather.

It's helpful to pre-tin the pads, then rest the connector in place and reheat.

Snap on the antenna adapter cable, and screw on the antenna to the other end.

Now, you can solder wires to the PN532 board. The other ends of each wire will be screwed into the terminal breakout FeatherWing.

Here a more in depth guide about setting up the board, however, we'll be using it in I2C mode, not SPI mode. 

Strip the wires on one end, then tin the wires. Insert them into the appropriate pin holes and solder.

Once soldered, trim off any excess from the bottom side, so the board will lay as flat as possible on the underside of the chess board.

Be sure to solder the mode jumpers on the PN532 breakout board as shown here to use I2C mode. Note the reference silkscreen on the board.

You can now strip the other ends of the wires and screw them into the terminals as shown.

Now, you're ready to code and test the reader!

This guide was first published on Aug 25, 2017. It was last updated on Aug 25, 2017. This page (Build the Reader Circuit) was last updated on Aug 11, 2019.