uv_sensor_basic.py

#!/usr/bin/env python3
"""
Basic UV Sensor Script
Simple script to read UV data from VEML6075 sensor
"""

import time
import json
from datetime import datetime
from smbus2 import SMBus

# I2C Configuration
I2C_BUS = 3  # Changed from 1 to 3 - UV sensor is on bus 3
VEML6075_ADDR = 0x10

# VEML6075 UV sensor registers
REG_CONF = 0x00
REG_UVB = 0x09
VEML6075_CONF_100MS = 0x00

class UVSensor:
    def __init__(self, bus, address, sensor_name):
        self.bus = bus
        self.address = address
        self.sensor_name = sensor_name
        self.working = False
        self.initialize()
    
    def initialize(self):
        """Initialize VEML6075 sensor"""
        try:
            # Set configuration for 100ms integration time
            self.bus.write_word_data(self.address, REG_CONF, VEML6075_CONF_100MS)
            time.sleep(0.2)
            
            # Verify configuration
            conf = self.bus.read_word_data(self.address, REG_CONF)
            if conf == VEML6075_CONF_100MS:
                self.working = True
                print(f"✅ {self.sensor_name} UV sensor initialized successfully")
            else:
                print(f"❌ {self.sensor_name} UV sensor configuration failed")
        except Exception as e:
            print(f"❌ Failed to initialize {self.sensor_name} UV sensor: {e}")
    
    def read_uvb(self):
        """Read UVB level"""
        if not self.working:
            return None
        
        try:
            # Read UVB data (16-bit)
            val = self.bus.read_word_data(self.address, REG_UVB)
            # Swap bytes (little endian to big endian)
            uvb = ((val & 0xFF) << 8) | (val >> 8)
            return uvb
        except Exception as e:
            print(f"Error reading {self.sensor_name} UVB: {e}")
            return None
    
    def get_uv_index(self, uvb_value):
        """Convert UVB counts to UV Index (approximate)"""
        if uvb_value is None:
            return None
        
        # This is an approximate conversion - actual conversion depends on sensor calibration
        # VEML6075 typically needs calibration for accurate UV Index
        uv_index = uvb_value / 100.0  # Rough approximation
        return round(uv_index, 2)

def main():
    print("🌞 Starting Basic UV Sensor...")
    
    # Initialize I2C bus
    try:
        bus = SMBus(I2C_BUS)
        print(f"✅ I2C bus {I2C_BUS} initialized")
    except Exception as e:
        print(f"❌ Failed to initialize I2C bus: {e}")
        return
    
    # Initialize UV sensor
    try:
        uv_sensor = UVSensor(bus, VEML6075_ADDR, "VEML6075")
        if not uv_sensor.working:
            print("❌ UV sensor not working. Exiting.")
            return
    except Exception as e:
        print(f"❌ Failed to initialize UV sensor: {e}")
        return
    
    print("📡 Starting UV data collection...")
    print("Press Ctrl+C to stop")
    print("-" * 50)
    
    try:
        while True:
            timestamp = datetime.now().isoformat()
            
            # Read UV sensor
            uvb_value = uv_sensor.read_uvb()
            uv_index = uv_sensor.get_uv_index(uvb_value)
            
            if uvb_value is not None:
                print(f"📊 UVB Counts: {uvb_value}")
                print(f"🌡️  UV Index: {uv_index}")
                print(f"⏰ Timestamp: {timestamp}")
                
                # Create data dictionary
                data = {
                    "sensor": "VEML6075",
                    "uvb_counts": uvb_value,
                    "uv_index": uv_index,
                    "timestamp": timestamp
                }
                
                # Save to JSON file (optional)
                with open("uv_data.json", "w") as f:
                    json.dump(data, f, indent=2)
                
                print("-" * 50)
            else:
                print("⚠️ Failed to read UV sensor data")
            
            # Wait before next reading
            time.sleep(2)  # Read every 2 seconds
            
    except KeyboardInterrupt:
        print("\n🛑 Stopping UV sensor...")
    except Exception as e:
        print(f"❌ Error in main loop: {e}")
    finally:
        bus.close()
        print("👋 UV sensor stopped")

if __name__ == "__main__":
    main()