Datasheet

ManualsBrandsAdafruit ManualsAdafruitRFM95W LoRa Radio Transceiver

That's all there is to the basic RFM69 radio usage!

Remember the CircuitPython module is designed for sending and

receiving small up to 60 byte control messages and not large or high bandwidth amounts of data.

Here's a complete example of sending a message and waiting to receive and print any received messages. Save this

as main.py on your board and open the serial REPL to see it print data and any received messages. If you have two

boards and radios setup to run this code at the same time they'll send each other a message on start up!

# Simple example to send a message and then wait indefinitely for messages

# to be received. This uses the default RadioHead compatible GFSK_Rb250_Fd250

# modulation and packet format for the radio.

# Author: Tony DiCola

import board

import busio

import digitalio

import adafruit_rfm69

# Define radio parameters.

RADIO_FREQ_MHZ = 915.0 # Frequency of the radio in Mhz. Must match your

# module! Can be a value like 915.0, 433.0, etc.

# Define pins connected to the chip, use these if wiring up the breakout according to the guide:

CS = digitalio.DigitalInOut(board.D5)

RESET = digitalio.DigitalInOut(board.D6)

# Or uncomment and instead use these if using a Feather M0 RFM69 board

# and the appropriate CircuitPython build:

#CS = digitalio.DigitalInOut(board.RFM69_CS)

#RESET = digitalio.DigitalInOut(board.RFM69_RST)

# Initialize SPI bus.

spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)

# Initialze RFM radio

rfm69 = adafruit_rfm69.RFM69(spi, CS, RESET, RADIO_FREQ_MHZ)

# Optionally set an encryption key (16 byte AES key). MUST match both

# on the transmitter and receiver (or be set to None to disable/the default).

rfm69.encryption_key = b'\x01\x02\x03\x04\x05\x06\x07\x08\x01\x02\x03\x04\x05\x06\x07\x08'

# Print out some chip state:

print('Temperature: {0}C'.format(rfm69.temperature))

print('Frequency: {0}mhz'.format(rfm69.frequency_mhz))

print('Bit rate: {0}kbit/s'.format(rfm69.bitrate/1000))

print('Frequency deviation: {0}hz'.format(rfm69.frequency_deviation))

# Send a packet. Note you can only send a packet up to 60 bytes in length.

# This is a limitation of the radio packet size, so if you need to send larger

# amounts of data you will need to break it into smaller send calls. Each send

# call will wait for the previous one to finish before continuing.

rfm69.send('Hello world!\r\n')

print('Sent hello world message!')

# Wait to receive packets. Note that this library can't receive data at a fast

# rate, in fact it can only receive and process one 60 byte packet at a time.

# This means you should only use this for low bandwidth scenarios, like sending

# and receiving a single message at a time.

print('Waiting for packets...')

https://learn.adafruit.com/adafruit-rfm69hcw-and-rfm96-rfm95-rfm98-lora-packet-padio-

breakouts

Page 46 of 70