Files
nebuleair_pro_4g/NPM/get_data_modbus_v2.py
PaulVua 6622be14ad update
2025-02-18 12:05:43 +01:00

189 lines
6.3 KiB
Python

'''
_ _ ____ __ __
| \ | | _ \| \/ |
| \| | |_) | |\/| |
| |\ | __/| | | |
|_| \_|_| |_| |_|
Script to get NPM data via Modbus
need parameter: port
/usr/bin/python3 /var/www/nebuleair_pro_4g/NPM/get_data_modbus_v2.py
Modbus RTU
[Slave Address][Function Code][Starting Address][Quantity of Registers][CRC]
Pour récupérer
les concentrations en PM1, PM10 et PM2.5 (a partir du registre 0x38)
les 5 cannaux
la température et l'humidité à l'intérieur du capteur
Donnée actualisée toutes les 10 secondes
Request
\x01\x03\x00\x38\x00\x55\...\...
\x01 Slave Address (slave device address)
\x03 Function code (read multiple holding registers)
\x00\x38 Starting Address (The request starts reading from holding register address x38 or 56)
\x00\x55 Quantity of Registers (Requests to read x55 or 85 consecutive registers starting from address 56)
\...\... Cyclic Redundancy Check (checksum )
'''
import serial
import requests
import json
import sys
import crcmod
import sqlite3
# Connect to the SQLite database
conn = sqlite3.connect("/var/www/nebuleair_pro_4g/sqlite/sensors.db")
cursor = conn.cursor()
def load_config(config_file):
try:
with open(config_file, 'r') as file:
config_data = json.load(file)
return config_data
except Exception as e:
print(f"Error loading config file: {e}")
return {}
# Load the configuration data
config_file = '/var/www/nebuleair_pro_4g/config.json'
config = load_config(config_file)
npm_solo_port = config.get('NPM_solo_port', '') #port du NPM solo
ser = serial.Serial(
port=npm_solo_port,
baudrate=115200,
parity=serial.PARITY_EVEN,
stopbits=serial.STOPBITS_ONE,
bytesize=serial.EIGHTBITS,
timeout = 0.5
)
# Define Modbus CRC-16 function
crc16 = crcmod.predefined.mkPredefinedCrcFun('modbus')
# Request frame without CRC
data = b'\x01\x03\x00\x38\x00\x55'
# Calculate CRC
crc = crc16(data)
crc_low = crc & 0xFF
crc_high = (crc >> 8) & 0xFF
# Append CRC to the frame
request = data + bytes([crc_low, crc_high])
#print(f"Request frame: {request.hex()}")
ser.write(request)
#GET RTC TIME from SQlite
cursor.execute("SELECT * FROM timestamp_table LIMIT 1")
row = cursor.fetchone() # Get the first (and only) row
rtc_time_str = row[1] # '2025-02-07 12:30:45'
while True:
try:
byte_data = ser.readline()
formatted = ''.join(f'\\x{byte:02x}' for byte in byte_data)
#print(formatted)
# Register base (56 = 0x38)
REGISTER_START = 56
# Function to extract 32-bit values from Modbus response
def extract_value(byte_data, register, scale=1, single_register=False, round_to=None):
"""Extracts a value from Modbus response.
- `register`: Modbus register to read.
- `scale`: Value is divided by this (e.g., `1000` for PM values).
- `single_register`: If `True`, only reads 16 bits (one register).
"""
offset = (register - REGISTER_START) * 2 + 3 # Calculate byte offset
if single_register:
value = int.from_bytes(byte_data[offset:offset+2], byteorder='big')
else:
lsw = int.from_bytes(byte_data[offset:offset+2], byteorder='big')
msw = int.from_bytes(byte_data[offset+2:offset+4], byteorder='big')
value = (msw << 16) | lsw # 32-bit value
value = value / scale # Apply scaling
if round_to == 0:
return int(value) # Convert to integer to remove .0
elif round_to is not None:
return round(value, round_to) # Apply normal rounding
else:
return value # No rounding if round_to is None
# 10-sec PM Concentration (PM1, PM2.5, PM10)
pm1_10s = extract_value(byte_data, 56, 1000, round_to=1)
pm25_10s = extract_value(byte_data, 58, 1000, round_to=1)
pm10_10s = extract_value(byte_data, 60, 1000, round_to=1)
#print("10 sec concentration:")
#print(f"PM1: {pm1_10s}")
#print(f"PM2.5: {pm25_10s}")
#print(f"PM10: {pm10_10s}")
# 1-min PM Concentration
pm1_1min = extract_value(byte_data, 68, 1000, round_to=1)
pm25_1min = extract_value(byte_data, 70, 1000, round_to=1)
pm10_1min = extract_value(byte_data, 72, 1000, round_to=1)
#print("1 min concentration:")
#print(f"PM1: {pm1_1min}")
#print(f"PM2.5: {pm25_1min}")
#print(f"PM10: {pm10_1min}")
# Extract values for 5 channels
channel_1 = extract_value(byte_data, 128, round_to=0) # 0.2 - 0.5μm
channel_2 = extract_value(byte_data, 130, round_to=0) # 0.5 - 1.0μm
channel_3 = extract_value(byte_data, 132, round_to=0) # 1.0 - 2.5μm
channel_4 = extract_value(byte_data, 134, round_to=0) # 2.5 - 5.0μm
channel_5 = extract_value(byte_data, 136, round_to=0) # 5.0 - 10.0μm
#print(f"Channel 1 (0.2->0.5): {channel_1}")
#print(f"Channel 2 (0.5->1.0): {channel_2}")
#print(f"Channel 3 (1.0->2.5): {channel_3}")
#print(f"Channel 4 (2.5->5.0): {channel_4}")
#print(f"Channel 5 (5.0->10.): {channel_5}")
# Retrieve relative humidity from register 106 (0x6A)
relative_humidity = extract_value(byte_data, 106, 100, single_register=True)
#print(f"Internal Relative Humidity: {relative_humidity} %")
# Retrieve temperature from register 106 (0x6A)
temperature = extract_value(byte_data, 107, 100, single_register=True)
#print(f"Internal temperature: {temperature} °C")
cursor.execute('''
INSERT INTO data_NPM_5channels (timestamp,PM_ch1, PM_ch2, PM_ch3, PM_ch4, PM_ch5) VALUES (?,?,?,?,?,?)'''
, (rtc_time_str,channel_1,channel_2,channel_3,channel_4,channel_5))
cursor.execute('''
INSERT INTO data_NPM (timestamp,PM1, PM25, PM10, temp_npm, hum_npm) VALUES (?,?,?,?,?,?)'''
, (rtc_time_str,pm1_10s,pm25_10s,pm10_10s,temperature,relative_humidity ))
# Commit and close the connection
conn.commit()
break
except KeyboardInterrupt:
print("User interrupt encountered. Exiting...")
time.sleep(3)
exit()
except:
# for all other kinds of error, but not specifying which one
print("Unknown error...")
time.sleep(3)
exit()
conn.close()