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// GUVA-S12SD UV Sensor - Arduino Example
// SIG Pin: A0, VCC: 5V, GND: GND
// UV Index is approximately the output voltage in mV divided by 100

const int sigPin = A0;
const int numSamples = 16;

void setup() {
  Serial.begin(9600);
}

void loop() {
  // Average several readings to smooth out ADC noise
  long total = 0;
  for (int i = 0; i < numSamples; i++) {
    total += analogRead(sigPin);
    delay(2);
  }
  float raw = total / (float)numSamples;

  // Convert the 10-bit reading (0-1023) to millivolts (5V reference)
  float millivolts = raw * (5000.0 / 1023.0);

  // Approximate solar UV Index: mV / 100
  float uvIndex = millivolts / 100.0;

  Serial.print("Voltage: ");
  Serial.print(millivolts, 0);
  Serial.print(" mV | UV Index: ");
  Serial.println(uvIndex, 1);

  delay(1000);
}

# GUVA-S12SD UV Sensor - ESP32 MicroPython Example
# SIG Pin: GPIO 34 (ADC1_CH6), VCC: 3.3V, GND: GND
# UV Index is approximately the output voltage in mV divided by 100

from machine import ADC, Pin
import time

adc = ADC(Pin(34))        # GPIO 34: input-only pin on ADC1
adc.atten(ADC.ATTN_11DB)  # Full 0-3.3V input range

while True:
    # Average several readings to smooth out ADC noise
    total_uv = 0
    for _ in range(16):
        total_uv += adc.read_uv()  # Factory-calibrated reading in microvolts
        time.sleep_ms(2)
    millivolts = total_uv / 16 / 1000

    # Approximate solar UV Index: mV / 100
    uv_index = millivolts / 100

    print("Voltage: {:.0f} mV | UV Index: {:.1f}".format(millivolts, uv_index))
    time.sleep(1)

#!/usr/bin/env python3
# GUVA-S12SD UV Sensor - Raspberry Pi + ADS1115 Example
# The Pi has no analog inputs, so an ADS1115 reads SIG over I2C.
# SIG -> ADS1115 A0, SDA -> GPIO 2, SCL -> GPIO 3
# Install the library first:
#   pip3 install adafruit-circuitpython-ads1x15

import time
import board
import busio
import adafruit_ads1x15.ads1115 as ADS
from adafruit_ads1x15.analog_in import AnalogIn

# I2C bus on GPIO 2 (SDA) / GPIO 3 (SCL)
i2c = busio.I2C(board.SCL, board.SDA)

# ADS1115 at default address 0x48, sensor SIG on channel A0
ads = ADS.ADS1115(i2c)
ads.gain = 2  # +/-2.048V full scale covers the 0-1V output with headroom
channel = AnalogIn(ads, ADS.P0)

try:
    while True:
        millivolts = channel.voltage * 1000

        # Approximate solar UV Index: mV / 100
        uv_index = millivolts / 100

        print("Voltage: {:.0f} mV | UV Index: {:.1f}".format(millivolts, uv_index))
        time.sleep(1)

except KeyboardInterrupt:
    print("Measurement stopped by user")

# GUVA-S12SD UV Sensor - Pico MicroPython Example
# SIG Pin: GP26 (ADC0, physical pin 31), VCC: 3V3(OUT), GND: GND
# UV Index is approximately the output voltage in mV divided by 100

from machine import ADC
import time

adc = ADC(26)             # GP26 = ADC0
CONVERSION = 3.3 / 65535  # read_u16() returns 0-65535 across 0-3.3V

while True:
    # Average several readings to smooth out ADC noise
    total = 0
    for _ in range(16):
        total += adc.read_u16()
        time.sleep_ms(2)
    millivolts = (total / 16) * CONVERSION * 1000

    # Approximate solar UV Index: mV / 100
    uv_index = millivolts / 100

    print("Voltage: {:.0f} mV | UV Index: {:.1f}".format(millivolts, uv_index))
    time.sleep(1)