Documentation

// ADS1115 - Read all 4 single-ended channels
// Requires: Adafruit ADS1X15 Library

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

Adafruit_ADS1115 ads;

void setup() {
  Serial.begin(9600);
  while (!Serial);

  if (!ads.begin(0x48)) {
    Serial.println("Failed to initialize ADS1115.");
    while (1);
  }

  // PGA = +/- 4.096V => 1 bit = 0.125 mV
  ads.setGain(GAIN_ONE);
  Serial.println("ADS1115 ready.");
}

void loop() {
  int16_t raw[4];
  float volts[4];
  for (int i = 0; i < 4; i++) {
    raw[i] = ads.readADC_SingleEnded(i);
    volts[i] = ads.computeVolts(raw[i]);
    Serial.print("A");
    Serial.print(i);
    Serial.print(": ");
    Serial.print(raw[i]);
    Serial.print("  ");
    Serial.print(volts[i], 4);
    Serial.print(" V   ");
  }
  Serial.println();
  delay(500);
}

// ADS1115 on ESP32 via I2C (GPIO21 SDA, GPIO22 SCL)
// Requires: Adafruit ADS1X15 Library

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

Adafruit_ADS1115 ads;

void setup() {
  Serial.begin(115200);
  Wire.begin(21, 22);

  if (!ads.begin(0x48)) {
    Serial.println("ADS1115 not found.");
    while (1);
  }
  ads.setGain(GAIN_ONE); // +/- 4.096V
  Serial.println("ADS1115 ready.");
}

void loop() {
  for (int i = 0; i < 4; i++) {
    int16_t raw = ads.readADC_SingleEnded(i);
    float v   = ads.computeVolts(raw);
    Serial.printf("A%d: raw=%d  %.4f V\n", i, raw, v);
  }
  Serial.println();
  delay(500);
}

# ADS1115 on Raspberry Pi via I2C
# Install: pip install adafruit-circuitpython-ads1x15
# Enable I2C: sudo raspi-config -> Interface Options -> I2C

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

i2c = busio.I2C(board.SCL, board.SDA)
ads = ADS.ADS1115(i2c, address=0x48)
ads.gain = 1  # +/- 4.096V

chans = [AnalogIn(ads, ADS.P0),
         AnalogIn(ads, ADS.P1),
         AnalogIn(ads, ADS.P2),
         AnalogIn(ads, ADS.P3)]

while True:
    for i, ch in enumerate(chans):
        print(f"A{i}: raw={ch.value}  {ch.voltage:.4f} V")
    print("-" * 30)
    time.sleep(1)

# ADS1115 on Raspberry Pi Pico via I2C0 (GP0 SDA, GP1 SCL)
# Upload an ads1x15.py driver to the Pico filesystem first.

from machine import I2C, Pin
from ads1x15 import ADS1115
import time

i2c = I2C(0, sda=Pin(0), scl=Pin(1), freq=400000)
print("I2C scan:", [hex(d) for d in i2c.scan()])

# gain=1 -> +/- 4.096V full scale
adc = ADS1115(i2c, address=0x48, gain=1)

while True:
    for channel in range(4):
        raw = adc.read(channel1=channel)
        volts = raw * 4.096 / 32767
        print("A{}: raw={}  {:.4f} V".format(channel, raw, volts))
    print("-" * 30)
    time.sleep(1)