使用 ESP32 找不到 MPU6050

Question

I would like to use my MPU6050 together with my ESP32 . (Link to the specific ESP Board)

It is not the first time for me using the MPU6050. I used it before in a project with an Arduino Uno and the MPU6050_light.h library. That worked perfectly. Now i'm trying it with my new ESP32.

I tried the MPU6050_light and Adafruit MPU6050 libraries but the first returns

MPU6050 status: 2

and the last throws the error:

Failed to find MPU6050 chip

The wires are definitely correct:

• GND->GND
• V3V->VCC
• SDA->PIN 21 (SDA PIN)
• SCL->PIN 22 (SCL PIN)

I used an I2C scanner to check if the MPU is found and what adress it has. And that worked too. It is the standart adress 0x68 . I observed that when I pull out one wire and than connecting it again, the found adress changes to 0x69 .

So the MPU was found. Has anyone any idea what could be the solution to my problem?

Code with MPU6050_light.h

#include <Arduino.h>
#include <MPU6050_light.h>
#include "Wire.h"

MPU6050 mpu(Wire);

long angle = 0;
unsigned long timer = 0;

void gyroSetUp()
{
  byte status = mpu.begin();
  Serial.print("MPU6050 status: ");
  Serial.println(status);
  while (status != 0)
  {
  } // stop everything if could not connect to MPU6050

  Serial.println("Calculating offsets, do not move MPU6050");
  delay(1000);
  mpu.calcOffsets(true, true); // gyro and accelero
  Serial.println("Done!\n");
}

void PrintAngles()
{
  Serial.print("X: ");
  Serial.print(mpu.getAngleX());
  Serial.print("\tY: ");
  Serial.print(mpu.getAngleY());
  Serial.print("\tZ: ");
  Serial.print(mpu.getAngleZ());
  Serial.print("\n");
}

void setup()
{
  Serial.begin(115200);

  Serial.println("Starting");
  Wire.begin();

  gyroSetUp();
}

void loop()
{
  mpu.update();

  if ((millis() - timer) > 1000)
  {
    PrintAngles();
    timer = millis();
  }
}

Code with Adafruit MPU6050

/* Get tilt angles on X and Y, and rotation angle on Z
 * Angles are given in degrees
 *
 * License: MIT
 */

#include "Wire.h"
#include <Adafruit_MPU6050.h>
#include <Adafruit_Sensor.h>

Adafruit_MPU6050 mpu;
sensors_event_t a, g, temp;
float gyroX, gyroY, gyroZ;
float gyroXerror = 0.07;
float gyroYerror = 0.03;
float gyroZerror = 0.01;
unsigned long lastTime = 0;
unsigned long gyroDelay = 10;

void initMPU()
{
  if (!mpu.begin())
  {
    Serial.println("Failed to find MPU6050 chip");
    while (1)
    {
      delay(10);
    }
  }
  Serial.println("MPU6050 Found!");
}

void getGyroReadings()
{
  mpu.getEvent(&a, &g, &temp);

  float gyroX_temp = g.gyro.x;
  if (abs(gyroX_temp) > gyroXerror)
  {
    gyroX += gyroX_temp / 50.00;
  }

  float gyroY_temp = g.gyro.y;
  if (abs(gyroY_temp) > gyroYerror)
  {
    gyroY += gyroY_temp / 70.00;
  }

  float gyroZ_temp = g.gyro.z;
  if (abs(gyroZ_temp) > gyroZerror)
  {
    gyroZ += gyroZ_temp / 90.00;
  }

  Serial.print("X: ");
  Serial.print(String(gyroX));
  Serial.print("\tY: ");
  Serial.print(String(gyroY));
  Serial.print("\tZ: ");
  Serial.print(String(gyroZ));
  Serial.print("\n");
}

void setup()
{
  Serial.begin(115200);
  initMPU();
}

void loop()
{
  if ((millis() - lastTime) > gyroDelay)
  {
    getGyroReadings();
    lastTime = millis();
  }
}

Answer 1

I found a fix for my specific problem. It took 4h of my lifetime. If you use the MPU6050_light.h there is a wrong function in the example-sketch:

mpu.calcOffsets();

You have to change it to:

mpu.calcOffsets(true, true);

I don't understand why this function is designed in that way, but it is ok to use it without parameters.

I still don't know why the other library won't work, but I hope I've saved others time in the future.