Update to ESP32-PoE

ESP32-PoE-Test2/ESP32-PoE-Test2.ino

@@ -0,0 +1,51 @@
+#include <driver/adc.h>
+
+
+float battery_read()
+{
+    //read battery voltage per %
+    long sum = 0;                  // sum of samples taken
+    float voltage = 0.0;           // calculated voltage
+    float output = 0.0;            //output value
+    const float battery_max = 3.6; //maximum voltage of battery
+    const float battery_min = 3.3; //minimum voltage of battery before shutdown
+
+    float R1 = 470000.0; // resistance of R1 (100K)
+    float R2 = 470000.0;  // resistance of R2 (10K)
+
+    for (int i = 0; i < 500; i++)
+    {
+        sum += adc1_get_voltage(ADC1_CHANNEL_7);
+        delayMicroseconds(1000);
+    }
+    Serial.print("Out :");
+    Serial.println(sum);
+    // calculate the voltage
+    voltage = sum / (float)500;
+    voltage = (voltage * 1.1) / 4096.0; //for internal 1.1v reference
+    // use if added divider circuit
+    voltage = voltage / (R2/(R1+R2));
+    //round value by two precision
+    voltage = roundf(voltage * 100) / 100;
+    Serial.print("voltage: ");
+    Serial.println(voltage, 2);
+    output = ((voltage - battery_min) / (battery_max - battery_min)) * 100;
+    if (output < 100)
+        return output;
+    else
+        return 100.0f;
+}
+
+void setup()
+{
+    adc1_config_width(ADC_WIDTH_12Bit);
+    adc1_config_channel_atten(ADC1_CHANNEL_7, ADC_ATTEN_11db); //set reference voltage to internal
+    Serial.begin(115200);
+}
+
+void loop()
+{
+    Serial.print("Battery Level: ");
+    Serial.println(battery_read(), 2);
+    delay(1000);
+}