I am working with Si7021 I2C HUMIDITY AND TEMPERATURE SENSOR. I have few questions about this sensor.
1. I am not able to get an acknowledgement from the sensor for start signal sent by the controller. Please provide a sample c code for interfacing with Atmega microcontroller.
2. The SDA and SCL lines should be pulled up t0 3.3V or 5V?
3. Is it possible to change the address of the sensor and have two such sensors on the same I2C line?
4. At what frequency should the communication between the controller and sensor take place?
5. How much time does the sensor take on an average to get new temperature/humidity reading?
Example source code is under the Tools tab in the Software and Drivers area of the following link:
The product datasheet has more details regarding response time, recommended I2C configuration, and addressing.
Simplicity Studio has example projects which utilize the Si7021 RHT Sensor on the STK. Those projects have example driver files for the RHT Sensor. You can open the example project for your STK, or you can reference the drive files in simplicity studio. When you download Studio v5, the Si7013.c/h files can be found here: