Donald asked 4 years ago
I2C
The ESP32 has two I2C channels and any pin can be set as SDA or SCL. When using the ESP32 with the Arduino IDE, the default I2C pins are:
- GPIO 21 (SDA)
- GPIO 22 (SCL)
If you want to use other pins, when using the wire library, you just need to call:
Wire.begin(SDA, SCL);
So, if I’m working on a project that is already using 21 and 22 (like the DS3231 RTC) and I want to add another I2C sensor/device, I would use the Wire function call like
Wire.begin(12,13);
which would assign SDA = 12 and SCL = 13?
Donald answered 4 years ago
I think I got a handle on it now.
If you want to use other pins, when using the wire library, you #define the pins, like this:
#define SDA 33
#define SCL 32
and in the setup() you use them with this:
Wire.begin(SDA, SCL)
Sara Santos Staff answered 4 years ago
Hi.
If the sensors have different I2C addresses, which is probable, you can use the same pins.
Alternatively, you can use different pins without any problem.
We have a guide about I2C with the ESP32 that you might find useful:
ESP32 I2C Communication: Set Pins, Multiple Bus Interfaces and Peripherals (Arduino IDE)
Regards,
Sara