LoRa Raspberry Pi Setup

This guide assumes that you've gotten your Raspberry Pi up and running, and have CircuitPython installed.

Installing CircuitPython Libraries

We're running CircuitPython on the Raspberry Pi, installing the libraries for radio communication is simple.

To install the library for the display, enter the following into the terminal:

sudo pip3 install adafruit-circuitpython-ssd1306

You'll also need to install the framebuf module in order to write to the display. 

sudo pip3 install adafruit-circuitpython-framebuf

To install the library for the RFM9x Module, enter the following into the terminal:

sudo pip3 install adafruit-circuitpython-rfm9x

RFM9x Connection Test!

Do not use this if you have a RFM69 Radio

The following code is for checking if the RFM9x radio is set up for transmitting and receiving. Save the code on your Pi as rfm9x_check.py.

"""
Wiring Check, Pi Radio w/RFM9x

Learn Guide: https://learn.adafruit.com/lora-and-lorawan-for-raspberry-pi
Author: Brent Rubell for Adafruit Industries
"""
import time
import busio
from digitalio import DigitalInOut, Direction, Pull
import board
# Import the SSD1306 module.
import adafruit_ssd1306
# Import the RFM9x radio module.
import adafruit_rfm9x

# Button A
btnA = DigitalInOut(board.D5)
btnA.direction = Direction.INPUT
btnA.pull = Pull.UP

# Button B
btnB = DigitalInOut(board.D6)
btnB.direction = Direction.INPUT
btnB.pull = Pull.UP

# Button C
btnC = DigitalInOut(board.D12)
btnC.direction = Direction.INPUT
btnC.pull = Pull.UP

# Create the I2C interface.
i2c = busio.I2C(board.SCL, board.SDA)

# 128x32 OLED Display
display = adafruit_ssd1306.SSD1306_I2C(128, 32, i2c, addr=0x3c)
# Clear the display.
display.fill(0)
display.show()
width = display.width
height = display.height

# Configure RFM9x LoRa Radio
CS = DigitalInOut(board.CE1)
RESET = DigitalInOut(board.D25)
spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)

while True:
    # Clear the image
    display.fill(0)

    # Attempt to set up the RFM9x Module
    try:
        rfm9x = adafruit_rfm9x.RFM9x(spi, CS, RESET, 915.0)
        display.text('RFM9x: Detected', 0, 0, 1)
    except RuntimeError:
        # Thrown on version mismatch
        display.text('RFM9x: ERROR', 0, 0, 1)

    # Check buttons
    if not btnA.value:
        # Button A Pressed
        display.text('Ada', width-85, height-7, 1)
        display.show()
        time.sleep(0.1)
    if not btnB.value:
        # Button B Pressed
        display.text('Fruit', width-75, height-7, 1)
        display.show()
        time.sleep(0.1)
    if not btnC.value:
        # Button C Pressed
        display.text('Radio', width-65, height-7, 1)
        display.show()
        time.sleep(0.1)

    display.show()
    time.sleep(0.1)

You'll also want to download the font file, font5x8.bin, and copy it into the same directory as the script:

To use the code, enter the following in your terminal:

python3 rfm9x_check.py

Now to check the setup:

If the RFM9x/RFM69 is detected, the OLED will display Detected. You can test  the buttons by pressing them.

If the wiring of the radio module is incorrect - the display will show ERROR. Check over your wiring on the Wiring Page and re-run the test. You may also need to ensure the correct CircuitPython library is installed for the module. 

 

If the OLED does not turn on - first check that it is wired correctly. Then, make sure you enabled I2C from raspi-config and installed the required libraries (adafruit-circuitpython-framebufand adafruit-circuitpython-ssd1306).

With everything working, let's move on to using the radio.

This guide was first published on Jan 23, 2019. It was last updated on Jan 23, 2019. This page (LoRa Raspberry Pi Setup) was last updated on Feb 03, 2019.