SBOA631 August   2025 HDC1010 , HDC1080 , HDC2010 , HDC2021 , HDC2022 , HDC2080 , HDC3020 , HDC3020-Q1 , HDC3021 , HDC3021-Q1 , HDC3022 , HDC3022-Q1 , HDC3120 , HDC3120-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Digital I2C Interface Overview
    1. 2.1 Register Map Protocol
      1. 2.1.1 A Quick Overview of I2C Register Map Protocol
        1. 2.1.1.1 HDC1x
        2. 2.1.1.2 HDC2x
          1. 2.1.1.2.1 Interfacing in Trigger-On Demand Mode
          2. 2.1.1.2.2 Interfacing Using Auto Measurement Mode (AMM)
    2. 2.2 Command Protocol
      1. 2.2.1 HDC302x
        1. 2.2.1.1 Interfacing in Trigger-On Demand Mode (One-Shot)
        2. 2.2.1.2 Interfacing in Auto Measurement Mode (AMM)
        3.       How to Check Measurement Data With CRC
  6. 3Analog Interface Overview
    1. 3.1 HDC3120
  7. 4Summary
  8. 5Development Support and Documentation
    1. 5.1 Software Support
    2. 5.2 References
Interfacing Using Auto Measurement Mode (AMM)

This section outlines how to configure HDC2x devices to operate in Auto Measurement Mode (AMM) and highlights key differences compared to Trigger-On Demand mode.

In AMM, the device automatically performs measurements at a user-defined sampling frequency, eliminating the need for manual measurement triggers from the MCU. Unlike Trigger-On Demand, where each measurement must be initiated manually, AMM requires only a single trigger to start periodic conversions.

In this example, the HDC2010 is configured to sample once every 5 seconds (0.2Hz). This is accomplished by writing the appropriate setting to the Configuration Register (0x0E). An illustration of the Configuration Register setup is provided in Figure 2-5.

 Configuration Register for Auto Measurement Mode (AMM)Figure 2-5 Configuration Register for Auto Measurement Mode (AMM)
// set device to Auto Measurement Mode for 0.2Hz (1 sample/5 seconds)

Wire.beginTransmission(0x40); // start communication with HDC2x

Wire.write(0x0E); // point to register 0x0E (Measurement Config)
Wire.write(0x40); // write value to register

Wire.endTransmission(); // end communication

The Measurement Configuration Register uses the same configuration explained in the Trigger-On Demand section.

Visit the following link to view the full sample code for the HDC2x in Auto Measurement Mode.