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Merge pull request #10 from jerryneedell/jerryn_spreadf

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Fix configuration for Spreading Factor = 6
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foamyguy 2025-02-20 09:15:09 -06:00 committed by GitHub
commit 8f0b80e279
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24
adafruit_rfm/rfm9x.py
View file

@ -169,6 +169,8 @@ class RFM9x(RFMSPI):
auto_agc = RFMSPI.RegisterBits(_RF95_REG_26_MODEM_CONFIG3, offset=2, bits=1)
header_mode = RFMSPI.RegisterBits(_RF95_REG_1D_MODEM_CONFIG1, offset=0, bits=1)
low_datarate_optimize = RFMSPI.RegisterBits(_RF95_REG_26_MODEM_CONFIG3, offset=3, bits=1)
lna_boost_hf = RFMSPI.RegisterBits(_RF95_REG_0C_LNA, offset=0, bits=2)
@ -424,6 +426,11 @@ class RFM9x(RFMSPI):
else:
self.write_u8(0x2F, 0x44)
self.write_u8(0x30, 0)
# set low_datarate_optimize for signal duration > 16 ms
if 1000 / (self.signal_bandwidth / (1 << self.spreading_factor)) > 16:
self.low_datarate_optimize = 1
else:
self.low_datarate_optimize = 0
@property
def coding_rate(self) -> Literal[5, 6, 7, 8]:
@ -461,14 +468,21 @@ class RFM9x(RFMSPI):
if val == 6:
self.detection_optimize = 0x5
self.header_mode = 1 # enable implicit header mode
else:
self.detection_optimize = 0x3
self.header_mode = 0 # enable exlicit header mode
self.write_u8(_RF95_DETECTION_THRESHOLD, 0x0C if val == 6 else 0x0A)
self.write_u8(
_RF95_REG_1E_MODEM_CONFIG2,
((self.read_u8(_RF95_REG_1E_MODEM_CONFIG2) & 0x0F) | ((val << 4) & 0xF0)),
)
# set low_datarate_optimize for signal duration > 16 ms
if 1000 / (self.signal_bandwidth / (1 << self.spreading_factor)) > 16:
self.low_datarate_optimize = 1
else:
self.low_datarate_optimize = 0
@property
def enable_crc(self) -> bool:
@ -491,6 +505,16 @@ class RFM9x(RFMSPI):
self.read_u8(_RF95_REG_1E_MODEM_CONFIG2) & 0xFB,
)
@property
def payload_length(self) -> int:
"""Must be set when using Implicit Header Mode - required for SF = 6"""
return self.read_u8(_RF95_REG_22_PAYLOAD_LENGTH)
@payload_length.setter
def payload_length(self, val: int) -> None:
# Set payload length
self.write_u8(_RF95_REG_22_PAYLOAD_LENGTH, val)
@property
def crc_error(self) -> bool:
"""crc status"""

98
examples/rfm_lora_sf_base.py Normal file
View file

@ -0,0 +1,98 @@
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
# SPDX-License-Identifier: MIT
import time
import board
import busio
import digitalio
# 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.CE1)
RESET = digitalio.DigitalInOut(board.D25)
# Initialize SPI bus.
spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)
# Initialze RFM radio
# uncommnet the desired import and rfm initialization depending on the radio boards being used
# Use rfm9x for two RFM9x radios using LoRa
from adafruit_rfm import rfm9x
rfm = rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ)
rfm.radiohead = False # don't appent RadioHead heade
# set spreading factor
rfm.spreading_factor = 7
print("spreading factor set to :", rfm.spreading_factor)
print("low_datarate_optimize set to: ", rfm.low_datarate_optimize)
# rfm.signal_bandwidth = 500000
print("signal_bandwidth set to :", rfm.signal_bandwidth)
print("low_datarate_optimize set to: ", rfm.low_datarate_optimize)
if rfm.spreading_factor == 12:
rfm.xmit_timeout = 5
print("xmit_timeout set to: ", rfm.xmit_timeout)
if rfm.spreading_factor == 12:
rfm.receive_timeout = 5
elif rfm.spreading_factor > 7:
rfm.receive_timeout = 2
print("receive_timeout set to: ", rfm.receive_timeout)
rfm.enable_crc = True
# send startup message
message = bytes(f"startup message from base", "UTF-8")
if rfm.spreading_factor == 6:
payload = bytearray(40)
rfm.payload_length = len(payload)
payload[0 : len(message)] = message
rfm.send(
payload,
keep_listening=True,
)
else:
rfm.send(
message,
keep_listening=True,
)
# Wait to receive packets.
print("Waiting for packets...")
# initialize flag and timer
# set a delay before sending the echo packet
# avoide multibples of .5 second to minimize chances of node missing
# the packet between receive attempts
transmit_delay = 0.75
last_transmit_time = 0
packet_received = False
while True:
if rfm.payload_ready():
packet_received = False
packet = rfm.receive(timeout=None)
if packet is not None:
# Received a packet!
# Print out the raw bytes of the packet:
print(f"Received (raw payload): {packet}")
print([hex(x) for x in packet])
print(f"RSSI: {rfm.last_rssi}")
packet_received = True
last_transmit_time = time.monotonic()
if packet_received and ((time.monotonic() - last_transmit_time) > transmit_delay):
# send back the received packet
if rfm.spreading_factor == 6:
payload = bytearray(40)
rfm.payload_length = len(payload)
payload[0 : len(packet)] = packet
rfm.send(
payload,
keep_listening=True,
)
else:
rfm.send(
packet,
keep_listening=True,
)
packet_received = False

105
examples/rfm_lora_sf_node.py Normal file
View file

@ -0,0 +1,105 @@
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
# SPDX-License-Identifier: MIT
# Example to send a packet periodically between addressed nodes with ACK
# Author: Jerry Needell
#
import time
import board
import busio
import digitalio
# 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.CE1)
RESET = digitalio.DigitalInOut(board.D25)
# Initialize SPI bus.
spi = busio.SPI(board.SCK, MOSI=board.MOSI, MISO=board.MISO)
# Initialze RFM radio
# uncommnet the desired import and rfm initialization depending on the radio boards being used
# Use rfm9x for two RFM9x radios using LoRa
from adafruit_rfm import rfm9x
rfm = rfm9x.RFM9x(spi, CS, RESET, RADIO_FREQ_MHZ)
rfm.radiohead = False # Do not use RadioHead Header
# set spreading factor
rfm.spreading_factor = 7
print("spreading factor set to :", rfm.spreading_factor)
print("low_datarate_optimize set to: ", rfm.low_datarate_optimize)
# rfm.signal_bandwidth = 500000
print("signal_bandwidth set to :", rfm.signal_bandwidth)
print("low_datarate_optimize set to: ", rfm.low_datarate_optimize)
if rfm.spreading_factor == 12:
rfm.xmit_timeout = 5
print("xmit_timeout set to: ", rfm.xmit_timeout)
if rfm.spreading_factor == 12:
rfm.receive_timeout = 5
elif rfm.spreading_factor > 7:
rfm.receive_timeout = 2
print("receive_timeout set to: ", rfm.receive_timeout)
rfm.enable_crc = True
# set the time interval (seconds) for sending packets
transmit_interval = 10
# initialize counter
counter = 0
# send startup message from my_node
message = bytes(f"startup message from node", "UTF-8")
if rfm.spreading_factor == 6:
payload = bytearray(40)
rfm.payload_length = len(payload)
payload[0 : len(message)] = message
rfm.send(
payload,
keep_listening=True,
)
else:
rfm.send(
message,
keep_listening=True,
)
# Wait to receive packets.
print("Waiting for packets...")
# initialize flag and timer
last_transmit_time = time.monotonic()
while True:
# Look for a new packet: only accept if addresses to my_node
packet = rfm.receive()
# 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(f"Received (raw payload): {packet}")
print([hex(x) for x in packet])
print(f"RSSI: {rfm.last_rssi}")
# send reading after any packet received
if time.monotonic() - last_transmit_time > transmit_interval:
# reset timeer
last_transmit_time = time.monotonic()
# send a mesage to destination_node from my_node
message = bytes(f"message from node {counter}", "UTF-8")
if rfm.spreading_factor == 6:
payload = bytearray(40)
rfm.payload_length = len(payload)
payload[0 : len(message)] = message
rfm.send(
payload,
keep_listening=True,
)
else:
rfm.send(
message,
keep_listening=True,
)
counter += 1