In this example, we're using the Wire library to communicate with an I2C device with address 0x12 . We're writing data to the device, then reading data back from the device and printing it to the serial console.
| Problem | Solution | | :--- | :--- | | "No such file or directory" | You have the wrong board selected. Switch to "Arduino Uno." | | Multiple "Wire.h" conflicts | Delete duplicate Wire folders from your Documents/Arduino/libraries folder (keep only the one in the IDE installation). | | Compilation is slow | You don't need a new download. The library is fine. Check your PC's RAM. | | I2C scanning returns no devices | The library is working, but your physical wiring (SDA/SCL) or pull-up resistors are missing. | download wire.h library for arduino
delay(500);
If updating the board doesn't work, a clean install of the latest Arduino IDE usually restores the missing core files. In this example, we're using the Wire library
Now you can run a on Wire , an OLED on Wire1 , and a temperature array on Wire2 – no collisions. Switch to "Arduino Uno