Using Circuitpython on the Challenger RP2040 SubGHz to send and receive data packets.

# SPDX-FileCopyrightText: 2020 Jerry Needell for Adafruit Industries
# SPDX-License-Identifier: MIT
# Modified 2022 to directly work with Challenger RP2040 SubGHz boards

# Example to send a packet periodically between addressed nodes

import time
import board
import busio
import digitalio
import adafruit_rfm69

# set the time interval (seconds) for sending packets
transmit_interval = 10

# Define radio parameters.
RADIO_FREQ_MHZ = 868.0  # 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.
CS = digitalio.DigitalInOut(board.RFM69HCW_CS)
RESET = digitalio.DigitalInOut(board.RFM69HCW_RST)

# Initialize SPI bus.
spi = busio.SPI(board.RFM69HCW_SCK, MOSI=board.RFM69HCW_SDO, MISO=board.RFM69HCW_SDI)
# 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"
)

# set node addresses
rfm69.node = 1
rfm69.destination = 2
# initialize counter
counter = 0
# send a broadcast message from my_node with ID = counter
rfm69.send(
    bytes("Startup message {} from node {}".format(counter, rfm69.node), "UTF-8")
)

# Wait to receive packets.
print("Waiting for packets...")
now = time.monotonic()
while True:
    # Look for a new packet: only accept if addresses to my_node
    packet = rfm69.receive(with_header=True)
    # If no packet was received during the timeout then None is returned.
    if packet is not None:
        # Received a packet!
        # Print out the raw bytes of the packet:
        print("Received (raw header):", [hex(x) for x in packet[0:4]])
        print("Received (raw payload): {0}".format(packet[4:]))
        print("Received RSSI: {0}".format(rfm69.last_rssi))
    if time.monotonic() - now > transmit_interval:
        now = time.monotonic()
        counter = counter + 1
        # send a  mesage to destination_node from my_node
        rfm69.send(
            bytes(
                "message number {} from node {}".format(counter, rfm69.node), "UTF-8"
            ),
            keep_listening=True,
        )
        button_pressed = None