user34688: I connected Raspberry Pi 3 to an Arduino Uno through I2C. The Arduino Uno uses the I2C as slave.
When I connect AM2320 sensor (temperature and humidity) to the Arduino Uno, I am getting the response that the sensor is offline.
I tested the sensor on Raspberry Pi 3 and it is working fine. On the Raspberry Pi the address is 0x5c. On most libraries, the address is 0xb8. I have the same result when I tried these 2 addresses.
Do I have problem because Arduino Uno is working as slave?

user-1: You can do it. A single device like the Arduino can be both a slave and a master.
It's explained in great detail by Nick Gammon in http://www.gammon.com.au/i2c in the paragraph Communicating with other devices

34688: <p>I connected Raspberry Pi 3 to an Arduino Uno through I2C. The Arduino Uno uses the I2C as slave.</p>

<p>When I connect <a href="https://akizukidenshi.com/download/ds/aosong/AM2320.pdf" rel="nofollow noreferrer">AM2320 sensor</a> (temperature and humidity) to the Arduino Uno, I am getting the response that the sensor is offline.</p>

<p>I tested the sensor on Raspberry Pi 3 and it is working fine. On the Raspberry Pi the address is 0x5c. On most libraries, the address is 0xb8. I have the same result when I tried these 2 addresses.</p>

<p>Do I have problem because Arduino Uno is working as slave?</p>
 -1: <p>You can do it. A single device like the Arduino can be both a slave and a master.</p>

<p>It's explained in great detail by Nick Gammon in <a href="http://www.gammon.com.au/i2c" rel="nofollow noreferrer">http://www.gammon.com.au/i2c</a> in the paragraph <em>Communicating with other devices</em></p>
