ADS1115 code not executing

I have an ads1115 chip that is connected to my MCU (ESP32) via I2C that I am using the to read several analog signals. The library that I am using is Adafruit's: (Adafruit_ADS1X15) and I am just using their example code for "single ended conversion" shown below.

The problem is when I upload the code and look at the serial monitor nothing at all is printing, not even "hello" which is in the setup. I've verified that other projects are writing to the serial monitor just fine, so it is not an inability to write to the serial monitor. Is the code trying to establish an I2C connection and failing? My circuit is rather different so I will share, but since the ESPs I2C pins are at 3.3V I have to step down my ADC from 5V to 3.3V using a voltage translator.


Example Code

#include <Wire.h>
#include <Adafruit_ADS1X15.h>

Adafruit_ADS1115 ads;  /* Use this for the 16-bit version */

void setup()


  Serial.println("Getting single-ended readings from AIN0..3");
  Serial.println("ADC Range: +/- 6.144V (1 bit = 3mV/ADS1015, 0.1875mV/ADS1115)");

  // The ADC input range (or gain) can be changed via the following
  // functions, but be careful never to exceed VDD +0.3V max, or to
  // exceed the upper and lower limits if you adjust the input range!
  // Setting these values incorrectly may destroy your ADC!
  //                                                                ADS1015  ADS1115
  //                                                                -------  -------
  // ads.setGain(GAIN_TWOTHIRDS);  // 2/3x gain +/- 6.144V  1 bit = 3mV      0.1875mV (default)
  // ads.setGain(GAIN_ONE);        // 1x gain   +/- 4.096V  1 bit = 2mV      0.125mV
  // ads.setGain(GAIN_TWO);        // 2x gain   +/- 2.048V  1 bit = 1mV      0.0625mV
  // ads.setGain(GAIN_FOUR);       // 4x gain   +/- 1.024V  1 bit = 0.5mV    0.03125mV
  // ads.setGain(GAIN_EIGHT);      // 8x gain   +/- 0.512V  1 bit = 0.25mV   0.015625mV
  // ads.setGain(GAIN_SIXTEEN);    // 16x gain  +/- 0.256V  1 bit = 0.125mV  0.0078125mV

  if (!ads.begin()) {
    Serial.println("Failed to initialize ADS.");
    while (1);

void loop()
  int16_t adc0, adc1, adc2, adc3;
  float volts0, volts1, volts2, volts3;

  adc0 = ads.readADC_SingleEnded(0);
  //adc1 = ads.readADC_SingleEnded(1);
  //adc2 = ads.readADC_SingleEnded(2);
  //adc3 = ads.readADC_SingleEnded(3);

  //volts0 = ads.computeVolts(adc0);
  //volts1 = ads.computeVolts(adc1);
  //volts2 = ads.computeVolts(adc2);
  //volts3 = ads.computeVolts(adc3);

  Serial.print("AIN0: "); Serial.print(adc0); Serial.print("  "); Serial.print(volts0); Serial.println("V");
  //Serial.print("AIN1: "); Serial.print(adc1); Serial.print("  "); Serial.print(volts1); Serial.println("V");
  //Serial.print("AIN2: "); Serial.print(adc2); Serial.print("  "); Serial.print(volts2); Serial.println("V");
  //Serial.print("AIN3: "); Serial.print(adc3); Serial.print("  "); Serial.print(volts3); Serial.println("V");


Check the baudrate in the IDE. Check that nothing is connected to the serial pins used for serial com.

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I am embarrassed to admit that it was the baud rate. I just didn't verify this

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Be my guest in that club!