ESP32-S3 · MPU6050

ESP32-S3 MPU6050 Simulator: Wiring, Code and a Live Circuit

This is an MPU6050 accelerometer and gyroscope on a GY-521 board, wired to an ESP32-S3 DevKitC-1 over I2C and read live: the sketch wakes the chip and prints the three acceleration axes four times a second. In the editor, drag the pitch and roll sliders and watch gravity move between them.

Four wires: 3V3, GND, SDA to GPIO 8 and SCL to GPIO 9. The sketch talks to the registers with Wire, so nothing is hidden behind a library.

Run it in the editor Read the code

3.3 V logic
Library: Wire.h only
I2C address 0x68
SDA 8, SCL 9

ESP32-S3 · MPU6050live0.000 s 0.00x

Click to open it in the editor

The circuit itself, running on the simulator with the sketch below. Press what can be pressed; click anything else to open it in the editor.

Wiring the MPU6050 to the ESP32-S3

Every connection in the circuit above, with the board’s own pin names.

MPU6050 pin	ESP32-S3 pin	Why
VCC	3V3	The GY-521 board has a 3.3 V regulator, so it takes 3.3 or 5 V.
GND	G	Common ground.
SCL	GPIO 9	I2C clock.
SDA	GPIO 8	I2C data.
AD0	not connected	Low (the board’s own pull-down): address 0x68. Tie it high for 0x69.

On the ESP32-S3, Wire.begin() uses GPIO 8 for SDA and GPIO 9 for SCL. The silkscreen names each pin by its GPIO number, so the labels match the code. Powered from 3V3, the GY-521’s pull-ups hold SDA and SCL at 3.3 V, the ESP32-S3’s own level. Its regulator still works from 3.3 V, with a little less headroom.

Pins to leave alone on the ESP32-S3

GPIO 19 and 20 are the USB port’s data lines, GPIO 35 to 37 belong to the PSRAM on octal-PSRAM boards such as the N8R8, and GPIO 0, 3, 45 and 46 are strapping pins.

On a real bench

The DevKitC-1 has two USB sockets: UART for uploading and the serial monitor, USB for the S3’s own USB device. Plug into UART while you work with the MPU6050. The board is wide, so a single breadboard leaves only one row free on one side.

The code

The sketch the circuit above runs. Open it in the editor, change a line and press Run: it compiles in your browser.

MPU6050 on ESP32-S3 I2C

#include <Wire.h>

const int MPU = 0x68;   // AD0 low

int16_t read16() {
  int16_t high = Wire.read();
  return (high << 8) | Wire.read();
}

void setup() {
  Serial.begin(115200);
  Wire.begin();                 // SDA GPIO 8, SCL GPIO 9
  Wire.beginTransmission(MPU);
  Wire.write(0x6B);             // PWR_MGMT_1
  Wire.write(0);                // wake up: it starts asleep
  Wire.endTransmission();
  Serial.println("MPU6050 awake");
}

void loop() {
  Wire.beginTransmission(MPU);
  Wire.write(0x3B);             // ACCEL_XOUT_H, then Y, Z, temperature, gyro
  Wire.endTransmission(false);
  Wire.requestFrom(MPU, 6);
  int16_t ax = read16();
  int16_t ay = read16();
  int16_t az = read16();
  // At the default range, 16384 counts is 1 g.
  Serial.print("Accel x: ");
  Serial.print(ax);
  Serial.print("  y: ");
  Serial.print(ay);
  Serial.print("  z: ");
  Serial.println(az);
  delay(250);
}

The MPU6050 powers up asleep, and every reading is zero until register 0x6B is written with 0. That one write in setup() is the step most broken sketches are missing.

Reading starts at register 0x3B and the chip sends the bytes that follow in order: X, Y and Z acceleration, two bytes each, high byte first. endTransmission(false) keeps the bus between the address write and the read, so the three axes come from the same sample.

Lying flat and still, the board reads 0, 0 and 16384: one g straight down on Z. Tilt it with the pitch and roll sliders and the gravity moves between the axes. This sketch uses Wire directly; Adafruit_MPU6050.h and MPU6050.h also compile here, but the raw registers are what those libraries do underneath. Serial.begin(115200) opens the serial monitor. Serial is UART0 on the board’s UART socket, at 115200 baud in this sketch.

Common mistakes with the MPU6050 on the ESP32-S3

Not waking it up

Out of reset the chip is asleep and returns zeros on every axis. Write 0 to register 0x6B first. It is the single most common MPU6050 fault.

Wiring to the ESP8266’s I2C pins

Many MPU6050 tutorials were written for the ESP8266, with SDA on GPIO 4 and SCL on GPIO 5. On an ESP32-S3 DevKitC-1 Wire.begin() uses GPIO 8 and GPIO 9.

Expecting an angle from the gyro

The gyroscope measures how fast the board turns, in degrees per second, not which way it points. For tilt, use the arctangent of two acceleration axes; for a steady angle while moving, combine both with a complementary filter.

Questions and answers

Can I simulate an MPU6050 with an ESP32-S3 DevKitC-1?

Yes. The circuit at the top of this page is an ESP32-S3 DevKitC-1 with a MPU6050, running in your browser on a simulated ESP32-S3 (Xtensa LX7). The pitch and roll sliders tilt the simulated chip, so the acceleration on each axis is what gravity would give at that angle. Press Run it in the editor to change the wiring or the code; it is free and needs no account.

Which pins does the MPU6050 use on the ESP32-S3?

On the ESP32-S3, Wire.begin() uses GPIO 8 for SDA and GPIO 9 for SCL. The silkscreen names each pin by its GPIO number, so the labels match the code.

Why are all my readings zero?

The chip is still asleep: write 0 to register 0x6B. If the readings are -1 instead, nothing answered at 0x68, so check the wiring and the AD0 pin.

Can I use the Adafruit MPU6050 library?

Adafruit_MPU6050.h compiles here. This page reads the registers with Wire so the sketch shows what the chip actually does, and so it runs the same on every board.

Build your own MPU6050 project

Open this circuit in the editor, change the wiring or the code, and keep your version in a free account.

Start building free Open the editor