ADS111S Arduino Library

The ADS111S library provides an easy-to-use interface for interacting with the ADS111x series 16-bit Analog-to-Digital Converters (ADCs) over I2C. This library supports single-ended and differential analog input readings, configurable gain, data rate, operating mode, and comparator settings. It is designed to work seamlessly with the Arduino platform.

Supported ADC modules: ADS1115, ADS1114, ADS1113

Features

• Read single-ended or differential analog inputs.
• Configure programmable gain amplifier (PGA) settings (e.g., 6.144V, 4.096V, etc.).
• Set data rates from 8 SPS to 860 SPS.
• Control operating modes (continuous or single-shot).
• Configure the built-in comparator with threshold values, polarity, and latching options.
• Check sensor connectivity over I2C.

Installation

Using the Arduino Library Manager

1. Open the Arduino IDE.
2. Go to Sketch > Include Library > Manage Libraries.
3. Search for ADS111S.
4. Click Install to download and install the library.

Manual Installation

1. Download the latest release of this repository as a ZIP file.
2. In the Arduino IDE, go to Sketch > Include Library > Add .ZIP Library.
3. Select the downloaded ZIP file and click Open.
4. The library will be installed and ready to use.

Dependencies

• Arduino.h: Core Arduino library (included with the Arduino IDE).
• SensorHub.h: A custom library for I2C communication (ensure it’s installed or included in your project).

Usage

Basic Example

#include <ADS111S.h>

ADS111S adc; // Create an ADS111S object with default configuration

void setup() {
  Serial.begin(115200);
  
  // Initialize the ADC
  if (!adc.begin()) {
    Serial.println("Failed to detect ADS111S ADC!");
    while (1);
  }
  
  Serial.println("ADS111S ADC initialized successfully.");
}

void loop() {
  // Read single-ended analog input from pin A0
  uint16_t value = adc.readFrom(0);
  Serial.print("Analog Value (A0): ");
  Serial.println(value);
  
  delay(1000); // Wait 1 second
}

Custom Configuration Example

#include <ADS111S.h>

ADS111SCONFIG config = {
  .OS = ADS111S_OS_START_SINGLE,        // Single-shot mode
  .PGA = ADS111S_PGA_2_048V,            // Gain of 2.048V
  .MODE = ADS111S_MODE_SINGLE,          // Single-shot mode
  .DR = ADS111S_DR_128SPS,              // 128 samples per second
  .COMP_MODE = ADS111S_COMP_MODE_TRADITIONAL, // Traditional comparator
  .COMP_POL = ADS111S_COMP_POL_ACTIVE_LOW,    // Active-low polarity
  .COMP_LAT = ADS111S_COMP_LAT_NON_LATCHING,  // Non-latching
  .COMP_QUE = ADS111S_COMP_QUE_DISABLE        // Disable comparator queue
};

ADS111S adc; // Create an ADS111S object

void setup() {
  Serial.begin(115200);
  
  if (!adc.begin(config)) {
    Serial.println("Failed to detect ADS111S ADC!");
    while (1);
  }
  
  Serial.println("ADS111S ADC initialized with custom config.");
}

void loop() {
  // Read differential input between A0 and A1
  uint16_t diffValue = adc.readFromDifferential(0);
  Serial.print("Differential Value (A0-A1): ");
  Serial.println(diffValue);
  
  delay(1000);
}

API Reference

Constructor

• ADS111S(): Creates an ADS111S object with default configuration.
• ADS111S(ADS111SCONFIG config): Creates an ADS111S object with a custom configuration.

Methods

• bool begin(): Initializes the ADC with the default configuration. Returns true if successful.
• bool begin(ADS111SCONFIG config): Initializes the ADC with a custom configuration. Returns true if successful.
• uint16_t readFrom(uint8_t pin): Reads a single-ended analog input from the specified pin (0-3).
• uint16_t readFromDifferential(uint8_t pin): Reads a differential analog input from the specified pin pair (0-3).
• bool isConnected(): Checks if the ADC is detected over I2C.
• void setDataRate(uint8_t dataRate): Sets the data rate (e.g., ADS111S_DR_128SPS).
• void setGain(uint8_t gain): Sets the PGA gain (e.g., ADS111S_PGA_2_048V).
• void setMode(uint8_t mode): Sets the operating mode (e.g., ADS111S_MODE_SINGLE).
• void setComparatorMode(bool mode): Sets the comparator mode (traditional or window).
• void setComparatorPolarity(bool polarity): Sets the comparator polarity (active-low or active-high).
• void setComparatorLatching(bool latching): Enables or disables comparator latching.
• void setComparatorQueue(uint8_t queue): Sets the comparator queue behavior.
• void setThreshold(uint16_t low, uint16_t high): Sets the low and high threshold values for the comparator.
• float getVoltageGainInUse(): Returns the current voltage gain in use.

Configuration Structure

The ADS111SCONFIG struct allows customization of the ADC settings:

• OS: Operational status (e.g., ADS111S_OS_START_SINGLE).
• PGA: Programmable gain amplifier setting (e.g., ADS111S_PGA_2_048V).
• MODE: Operating mode (e.g., ADS111S_MODE_SINGLE).
• DR: Data rate (e.g., ADS111S_DR_128SPS).
• COMP_MODE: Comparator mode (e.g., ADS111S_COMP_MODE_TRADITIONAL).
• COMP_POL: Comparator polarity (e.g., ADS111S_COMP_POL_ACTIVE_LOW).
• COMP_LAT: Comparator latching (e.g., ADS111S_COMP_LAT_NON_LATCHING).
• COMP_QUE: Comparator queue (e.g., ADS111S_COMP_QUE_DISABLE).

Predefined Constants

Constants for configuration are defined in ADS111SDEFS.h. Examples include:

• Gain options: ADS111S_PGA_6_144V, ADS111S_PGA_4_096V, etc.
• Data rates: ADS111S_DR_8SPS, ADS111S_DR_860SPS, etc.
• I2C address: ADS111S_I2C_ADDR (default: 0x48).

Hardware Requirements

• Compatible with ADS111x series ADCs (supported ADCs are ADS1113, ADS1114, ADS1115).
• I2C interface (connect SDA and SCL to your Arduino’s I2C pins).
• Power supply: 2.0V to 5.5V (check your specific ADS111x model).

License

This library is released under the MIT License. Feel free to use, modify, and distribute it as needed.

Author

• Saurav Sajeev

Contributing

Contributions are welcome! Please submit a pull request or open an issue on the GitHub repository for suggestions, bug reports, or improvements.