BMP388 barometric pressure with ESP32

Supply 3.3-5 V Bus I2C I2C address 0x77 / 0x76 Measures pressure, temperature

Pins and ESP32 wiring

Pin	Role	ESP32 pin	Notes
VIN	Power	3V3
3VO	Not wired to the ESP32	—	3.3 V output of the on-board regulator. Leave unconnected
GND	Ground	GND
SCK	I2C clock (SCL)	D22	I2C SCL (SPI SCK)
SDO	Not wired to the ESP32	—	I2C address select: LOW = 0x76, HIGH or open = 0x77
SDI	I2C data (SDA)	D21	I2C SDA (SPI SDI)
CS	Not wired to the ESP32	—	Leave HIGH or unconnected for I2C
INT	Interrupt	D35	Interrupt output, optional

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 0x00: a genuine part answers 0x50. 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(0x77);
  bool found = Wire.endTransmission() == 0;
  Serial.println(found ? "BMP388 barometric pressure found at 0x77" : "Not found: check power, GND and SDA/SCL");
}

void loop() {}

Sources

Bosch BMP388 datasheet, Register 0x00 CHIP_ID (reads 0x50)
Bosch BMP388 datasheet, I2C address 0x76 (SDO = GND) or 0x77 (SDO = VDDIO)
Adafruit BMP388 guide, Pinout VIN, 3Vo, GND, SCK, SDO, SDI, CS, INT

Try it in 3D in BoardPilot

BoardPilot Part data (JSON)

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