Custom I²C Device¶
Lots of devices communicate using the I²C protocol. If you want to integrate
a device into ESPHome that uses this protocol you can pretty much use almost
all Arduino-based code because the Wire library is also available in ESPHome.
See the other custom component guides for how to register components and make them publish values.
#include "esphome.h"
class MyCustomComponent : public Component {
public:
void setup() override {
// Initialize the device here. Usually Wire.begin() will be called in here,
// though that call is unnecessary if you have an 'i2c:' entry in your config
Wire.begin();
}
void loop() override {
// Example: write the value 0x42 to register 0x78 of device with address 0x21
Wire.beginTransmission(0x21);
Wire.write(0x78);
Wire.write(0x42);
Wire.endTransmission();
}
};