Figure 2-1 HDC1080 Data Frame Example (Configuration Register)

In I2C-based sensors, the register map is a structured table of memory locations (registers) that define how the device is controlled and accessed. Each register has a unique address that the host can read from or write to, allowing direct interaction with the configuration of the sensor, status bits, and data. This organized layout makes it straightforward to adjust settings, retrieve measurements, and monitor flag bits. For the HDC1x and HDC2x devices, the data structure looks similar to that in Figure 2-1, where after sending the address byte, the controller must send the pointer register byte before the controller can read data from the sensor.

For more information on I2C, see the following document on I2C Basics.