98 lines
3.1 KiB
Python
98 lines
3.1 KiB
Python
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
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# SPDX-License-Identifier: MIT
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import time
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import board
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import busio
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import digitalio
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# Define radio parameters.
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RADIO_FREQ_MHZ = 915.0 # Frequency of the radio in Mhz. Must match your
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# module! Can be a value like 915.0, 433.0, etc.
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# Define pins connected to the chip, use these if wiring up the breakout according to the guide:
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CS = digitalio.DigitalInOut(board.CE1)
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RESET = digitalio.DigitalInOut(board.D25)
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# Initialize SPI bus.
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spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)
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# Initialze RFM radio
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# uncommnet the desired import and rfm initialization depending on the radio boards being used
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# Use rfm9x for two RFM9x radios using LoRa
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from adafruit_rfm import rfm9x
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rfm = rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ)
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rfm.radiohead = False # don't appent RadioHead heade
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# set spreading factor
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rfm.spreading_factor = 7
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print("spreading factor set to :", rfm.spreading_factor)
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print("low_datarate_optimize set to: ", rfm.low_datarate_optimize)
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# rfm.signal_bandwidth = 500000
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print("signal_bandwidth set to :", rfm.signal_bandwidth)
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print("low_datarate_optimize set to: ", rfm.low_datarate_optimize)
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if rfm.spreading_factor == 12:
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rfm.xmit_timeout = 5
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print("xmit_timeout set to: ", rfm.xmit_timeout)
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if rfm.spreading_factor == 12:
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rfm.receive_timeout = 5
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elif rfm.spreading_factor > 7:
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rfm.receive_timeout = 2
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print("receive_timeout set to: ", rfm.receive_timeout)
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rfm.enable_crc = True
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# send startup message
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message = bytes(f"startup message from base", "UTF-8")
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if rfm.spreading_factor == 6:
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payload = bytearray(40)
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rfm.payload_length = len(payload)
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payload[0 : len(message)] = message
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rfm.send(
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payload,
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keep_listening=True,
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)
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else:
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rfm.send(
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message,
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keep_listening=True,
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)
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# Wait to receive packets.
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print("Waiting for packets...")
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# initialize flag and timer
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# set a delay before sending the echo packet
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# avoide multibples of .5 second to minimize chances of node missing
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# the packet between receive attempts
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transmit_delay = 0.75
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last_transmit_time = 0
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packet_received = False
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while True:
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if rfm.payload_ready():
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packet_received = False
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packet = rfm.receive(timeout=None)
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if packet is not None:
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# Received a packet!
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# Print out the raw bytes of the packet:
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print(f"Received (raw payload): {packet}")
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print([hex(x) for x in packet])
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print(f"RSSI: {rfm.last_rssi}")
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packet_received = True
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last_transmit_time = time.monotonic()
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if packet_received and ((time.monotonic() - last_transmit_time) > transmit_delay):
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# send back the received packet
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if rfm.spreading_factor == 6:
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payload = bytearray(40)
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rfm.payload_length = len(payload)
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payload[0 : len(packet)] = packet
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rfm.send(
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payload,
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keep_listening=True,
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)
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else:
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rfm.send(
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packet,
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keep_listening=True,
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)
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packet_received = False
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