ESP8266 ESP-12E Test Boards A0 ADC Test

0V-1V ==> 0-1024 10bit ADC 
ESP8266 ESP-12E Test Boards A0 ADC

ADC Specifications

When referring to the ESP ADC pin you will often hear these different terms interchangeably:

• ADC (Analog-to-digital Converter)
• TOUT
• Pin6
• A0
• Analog Pin 0

All these terms refer to the same pin in the ESP8266 that is highlighted in the next section.

Currently, TOUT (Pin6) has a 10-bit precision and its input voltage range is 0 to 1.0 V when TOUT is connected to an external circuit.

參考 http://randomnerdtutorials.com/esp8266-adc-reading-analog-values-with-nodemcu/

//Tools -> Board -> Generic ESP8266 Module

//ESP8266 ESP-12E Test Boards A0 ADC Test Program
// The CDS (LDR is cutted off) on Active
//AO input Voltage Rabge 0-1V 
const int LDR = A0;

void setup() 
{
    Serial.begin(9600);
    pinMode(LDR, INPUT);
}

void loop()
{
    Serial.print("LDR: ");
    Serial.println(analogRead(LDR));   // 0V-1V ==> 0-1024 10bit ADC 
    delay(500);
}