Problem with many accelerometers at arduino mega (MPU6050 GY-521, Mega 2560)

Other Hardware Sensors
1

Hi everyone,

I've just start my work with Arduino and I'm trying to build measurement system with three or more accelerometers (MPU 6050).

I wrote simple code (Szkic_3-axis) based at Korneliusz Jarzębski code -http://www.jarzebski.pl/arduino/czujniki-i-sensory/3-osiowy-zyroskop-i-akcelerometr-mpu6050.html- but when I'm trying to do the same with Jeff Rowberg Script (SZKICOWNIK) -https://github.com/jrowberg/i2cdevlib/tree/master/Arduino/MPU6050- I have problem which I cannot understand because this code works with one accelerometers properly, but now I can't see any data...

Thats my problems with compilation:

In file included from C:\Users\Daniel\Documents\Arduino\SZKICOWNIK\SZKICOWNIK.ino:49:0:

C:\Users\Daniel\Documents\Arduino\libraries\MPU6050/MPU6050_6Axis_MotionApps20.h: In member function 'uint8_t MPU6050::dmpGetGravity(int16_t*, const uint8_t*)':

C:\Users\Daniel\Documents\Arduino\libraries\MPU6050/MPU6050_6Axis_MotionApps20.h:689:65: warning: integer overflow in expression [-Woverflow]

         - (int32_t)qI[2] * qI[2] + (int32_t)qI[3] * qI[3]) / (2 * 16384);

C:\Users\Daniel\Documents\Arduino\libraries\MPU6050/MPU6050.h:436:7: warning: type 'struct MPU6050' violates one definition rule [-Wodr]

 class MPU6050 {

       ^

C:\Users\Daniel\Documents\Arduino\libraries\MPU6050\MPU6050.h:436:7: note: a different type is defined in another translation unit

 class MPU6050 {

       ^

C:\Users\Daniel\Documents\Arduino\libraries\MPU6050/MPU6050.h:1026:18: note: the first difference of corresponding definitions is field 'dmpPacketBuffer'

         uint8_t *dmpPacketBuffer;

                  ^

C:\Users\Daniel\Documents\Arduino\libraries\MPU6050\MPU6050.h:436:7: note: a type with different number of fields is defined in another translation unit

 class MPU6050 {

       ^

I suppose that my problem is with DMP. Firstly I had connect every INT to 2 pin but now I was try connect every INT to another pin (2,3 and 4).

I've try to separate every value to another sensor:

#define INTERRUPT_PIN 2  // use pin 2 on Arduino Uno & most boards
#define INTERRUPT2_PIN 3
#define INTERRUPT3_PIN 4
#define GLOWKA 5  // use pin 5
#define TROJKAT 6  // use pin 6
#define DAMPER 7  // use pin 7
#define LED_PIN 13 // (Arduino is 13, Teensy is 11, Teensy++ is 6)
bool blinkState = false;
int Alfons = 1;  // Counter

// MPU control/status vars
bool dmpReady = false;  // set true if DMP init was successful
bool dmp2Ready = false;
bool dmp3Ready = false;
uint8_t mpuIntStatus;   // holds actual interrupt status byte from MPU
uint8_t mpu2IntStatus;
uint8_t mpu3IntStatus;
uint8_t devStatus;      // return status after each device operation (0 = success, !0 = error)
uint8_t dev2Status;
uint8_t dev3Status;
uint16_t packetSize;    // expected DMP packet size (default is 42 bytes)
uint16_t packet2Size;
uint16_t packet3Size;
uint16_t fifoCount;     // count of all bytes currently in FIFO
uint16_t fifo2Count;
uint16_t fifo3Count;
uint8_t fifoBuffer[64]; // FIFO storage buffer
uint8_t fifo2Buffer[64];
uint8_t fifo3Buffer[64];

But I've no idea what to do with "_BV(MPU6050_INTERRUPT_DMP_INT_BIT)":

if ((mpu2IntStatus & _BV(MPU6050_INTERRUPT_FIFO_OFLOW_BIT)) || fifo2Count >= 1024) {
          // reset so we can continue cleanly
          mpu2.resetFIFO();
          fifo2Count = mpu2.getFIFOCount();
          Serial.println(F("FIFO_2 overflow!\t"));
          Serial.println("Fifo2Count\t");
          Serial.println(fifo2Count);
          Serial.println("mpu2IntStatus\t");
          Serial.println(mpu2IntStatus);
          Serial.println("MPU6050_INTERRUPT_FIFO_OFLOW_BIT\t");
          Serial.println(MPU6050_INTERRUPT_FIFO_OFLOW_BIT);
      // otherwise, check for DMP data ready interrupt (this should happen frequently)
      } else if (mpu2IntStatus & _BV(MPU6050_INTERRUPT_DMP_INT_BIT)) {
          // wait for correct available data length, should be a VERY short wait
          while (fifo2Count < packet2Size) fifo2Count = mpu2.getFIFOCount();
  
          // read a packet from FIFO
          mpu2.getFIFOBytes(fifo2Buffer, packet2Size);
          
          // track FIFO count here in case there is > 1 packet available
          // (this lets us immediately read more without waiting for an interrupt)
          fifo2Count -= packet2Size;

Now I have no idea why it doesn't work or maybe I made something wrong?

SZKICOWNIK.ino (34 KB)

Szkic_3-axis.ino (3.55 KB)

Przechwytywanie1.PNG

2

For informed help, please read and follow the directions in the "How to use this forum" post.

3

You will find that reading the error messages can be very helpful. For example this one:

warning: integer overflow in expression
.... (2 * 16384);

On the standard Arduino, including Mega2560, integers are 16 bits, with values ranging from -32768 to 32767. The above expression results in integer overflow.

Evidently you are attempting to compile code that is either wrong, or targeted to a different processor. Go through all the messages, and fix the problems one by one.

But I've no idea what to do with "_BV(MPU6050_INTERRUPT_DMP_INT_BIT)":

Why would you want to do something with it? That constant is either defined somewhere, or it is not, in which case you are incorrectly mixing code and/or code libraries.

We strongly recommend that beginners start at the beginning, and work through some of the simple examples provided with the Arduino software development package, in order to learn the language and special features of the Arduino.