GY-BMP280 pressure + temperature with ESP32

Supply 3.3 V Bus I2C I2C address 0x76 / 0x77 Measures temperature, pressure

Pins and ESP32 wiring

Pin	Role	ESP32 pin	Notes
VCC	Power	3V3
GND	Ground	GND
SCL	I2C clock (SCL)	D22
SDA	I2C data (SDA)	D21
CSB	Not wired to the ESP32	—	Chip select. Leave unconnected (pulled HIGH on the board) to use I2C
SDO	Not wired to the ESP32	—	Address select: LOW = 0x76, HIGH = 0x77. Most boards default to 0x76

Suggested wiring for the 30-pin ESP32 DevKit, avoiding flash, input-only and strapping pins. BoardPilot checks it for you as you wire.

Check it is the real chip

Read register 0xD0: a genuine part answers 0x58. BoardPilot does this automatically in “Debug a problem”.

Starter code (Arduino)

#include <Wire.h>

void setup() {
  Serial.begin(115200);
  Wire.begin(21, 22);  // SDA = GPIO 21, SCL = GPIO 22
  Wire.beginTransmission(0x76);
  bool found = Wire.endTransmission() == 0;
  Serial.println(found ? "GY-BMP280 pressure + temperature found at 0x76" : "Not found: check power, GND and SDA/SCL");
}

void loop() {}

Sources

Bosch BMP280 datasheet, Register 0xD0 id (reads 0x58)
Bosch BMP280 datasheet, I2C interface: address 0x76 when SDO = GND, 0x77 when SDO = VDDIO

Try it in 3D in BoardPilot

BoardPilot Part data (JSON)

Part data: CC BY 4.0, free to reuse with credit to BoardPilot.