Perfect!

The quote is from this sample : Measuring and Reporting Battery Level

Use a 1MΩ (R1) and 470KΩ (R2) resistor in series, connected to the positive terminal on the battery and ground and then connected the tap point to the A0 input on the CPU.

The tap point could be bypassed with a 0.1 uF capacitor to keep the noise level low, at this otherwise high impedance point.

/**

• DESCRIPTION
• Sensor: CJMCU-GUVA-S12SD/CJMCU-S12D
• Sensor Arduino
• SIG -> A0
• GND -> GND
• VCC -> 5V or 3.3v
• part created by Henrik Ekblad henrik.ekblad@mysensors.org
• Copyright (C) 2013-2015 Sensnology AB
• Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
• part Original link : CSDN 博客链接.
• part by Tonbor august 2018
  */

// Enable debug prints to serial monitor
#define MY_DEBUG

// Enable and select radio type attached
#define MY_RADIO_NRF24
//#define MY_RADIO_NRF5_ESB
//#define MY_RADIO_RFM69
//#define MY_RADIO_RFM95

#include <MySensors.h>

#define UV_SENSOR_ANALOG_PIN 0

#define CHILD_ID_UV 0

uint32_t SLEEP_TIME = 30*1000; // Sleep time between reads (in milliseconds)

MyMessage uvMsg(CHILD_ID_UV, V_UV);

int lastSend =0;
int sensorValue;
long sum = 0;
int vout = 0;
int uv = 0;
int lastUV = -1;

void presentation()
{
// Send the sketch version information to the gateway and Controller
sendSketchInfo("UV Sensor", "1.3");

// Register all sensors to gateway (they will be created as child devices)
present(CHILD_ID_UV, S_UV);

}
void setup() {
Serial.begin(115000);
}
void loop()
{
uint32_t currentTime = millis();
sensorValue = 0;
sum = 0;
for (int i = 0 ; i < 1024 ; i++ ) {
sensorValue = analogRead(UV_SENSOR_ANALOG_PIN);
sum = sensorValue + sum;
delay(2);
}
vout = sum >> 10;
vout = vout * 4980.0 / 1024;
Serial.print("The Photocurrent value:");
Serial.print(vout);
Serial.println("mV");
if (vout < 50) {
uv = 0;
}
else if (vout < 227) {
uv = 1;
}
else if (vout < 318) {
uv = 2;
}
else if (vout < 408) {
uv = 3;
}
else if (vout < 503) {
uv = 4;
}
else if (vout < 606) {
uv = 5;
}
else if (vout < 696) {
uv = 6;
}
else if (vout < 795) {
uv = 7;
}
else if (vout < 881) {
uv = 8;
}
else if (vout < 976) {
uv = 9;
}
else if (vout < 1079) {
uv = 10;
}
else {
uv = 11;
}

//Send value to gateway if changed, or at least every 5 minutes
if ((uv != lastUV)||(currentTime-lastSend >= 5UL*60UL*1000UL)) {
	lastSend=currentTime;
	send(uvMsg.set(uv));
	lastUV = uv;
}

sleep(SLEEP_TIME);

}

Re: [0_1534265394169_UVSensor.ino](Uploading 100%) GUVA-S12SD UV sensor sketch required

[0_1534265424506_UVSensor.ino](Uploading 100%)

GUVA-S12SD UV sensor sketch made, hope to get response and help others, there was a question a year ago for a sketch by Tommas. Scatz suggested to post a sketch.