SPI Data Pins (Fixed)

The three SPI data pins (MOSI/MISO/SCK) are hardwired to these three pads, which are use for the default SPI interface on all Feathers:

SPI Control Pins (Flexible)

You also need three more pins to control the radio: IRQ, CS and RST.

Since there is no guaranteed pin that is consistently interrupt-capable across all Feather boards, we set it up so you can wire these three to any three pins available. For the non-Serial/IC pins on the right, we name them A thru F. We also indicate the RX/TX/SDA/SCL pins if you need to use those:

Three wires from IRQ, CS and RST will be soldered to three of these other points. Exactly which pins to connect are shown on the next page (it varies among Feather boards), this is merely to illustrate how the short soldered wires might look when installed:

Again: follow the directions on the next page; the jumpers shown above are not suitable for every Feather board.

RFM GPIO

There's some other GPIO pins that you may want to use - they can be configured to give you notice of things like packet completion or incoming data. They're all on the left. DIO0 is also known as IRQ so we don't have that duplicated on the left breakouts

Antenna

For an antenna, you have three options:

• Plain wire antenna (cut a quarter-wavelength piece and solder it into the pad/hole
• uFL connector (not included), which can be soldered and then used to attach a uFL antenna or adapter
• SMA edge-launch (not included), for use with any SMA connector