Arduino ide for esp8266 use MPU6050

[ehitil]

I use arduino-MPU6050-master library , No matter how I flip it my serial output is positive and I can't get negative numbers。

like this:

Xnorm = 0.08 Ynorm = 38.57 Znorm = 7.81
Xraw = 84.00 Yraw = 64588.00 Zraw = 13068.00
Xnorm = 0.14 Ynorm = 38.64 Znorm = 7.82
Xraw = 232.00 Yraw = 64724.00 Zraw = 12860.00
Xnorm = 0.18 Ynorm = 38.74 Znorm = 7.77
Xraw = 36.00 Yraw = 64540.00 Zraw = 13124.00
Xnorm = 0.03 Ynorm = 38.63 Znorm = 7.85
Xraw = 64744.00 Yraw = 65072.00 Zraw = 10928.00
Xnorm = 38.79 Ynorm = 38.95 Znorm = 6.97
Xraw = 65244.00 Yraw = 65080.00 Zraw = 13208.00
Xnorm = 39.00 Ynorm = 38.86 Znorm = 7.78
Xraw = 65284.00 Yraw = 64800.00 Zraw = 13284.00
Xnorm = 38.98 Ynorm = 38.78 Znorm = 7.91
Xraw = 65116.00 Yraw = 1248.00 Zraw = 12456.00
Xnorm = 39.03 Ynorm = 0.20 Znorm = 7.50
Xraw = 64716.00 Yraw = 64716.00 Zraw = 13124.00
Xnorm = 38.69 Ynorm = 38.82 Znorm = 7.83

[ehitil]

i use +-2g but "norm" data more than 2,i can not understand why？

[ehitil]

my code:

/*
MPU6050 Triple Axis Gyroscope & Accelerometer. Simple Accelerometer Example.
Read more: http://www.jarzebski.pl/arduino/czujniki-i-sensory/3-osiowy-zyroskop-i-akcelerometr-mpu6050.html
GIT: https://github.com/jarzebski/Arduino-MPU6050
Web: http://www.jarzebski.pl
(c) 2014 by Korneliusz Jarzebski
*/

#include <Wire.h>
#include <MPU6050.h>

MPU6050 mpu;

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

Serial.println("Initialize MPU6050");

while(!mpu.begin(MPU6050_SCALE_2000DPS, MPU6050_RANGE_2G))
{
Serial.println("Could not find a valid MPU6050 sensor, check wiring!");
delay(500);
}

// If you want, you can set accelerometer offsets
// mpu.setAccelOffsetX();
// mpu.setAccelOffsetY();
// mpu.setAccelOffsetZ();

checkSettings();
}

void checkSettings()
{
Serial.println();

Serial.print(" * Sleep Mode: ");
Serial.println(mpu.getSleepEnabled() ? "Enabled" : "Disabled");

Serial.print(" * Clock Source: ");
switch(mpu.getClockSource())
{
case MPU6050_CLOCK_KEEP_RESET: Serial.println("Stops the clock and keeps the timing generator in reset"); break;
case MPU6050_CLOCK_EXTERNAL_19MHZ: Serial.println("PLL with external 19.2MHz reference"); break;
case MPU6050_CLOCK_EXTERNAL_32KHZ: Serial.println("PLL with external 32.768kHz reference"); break;
case MPU6050_CLOCK_PLL_ZGYRO: Serial.println("PLL with Z axis gyroscope reference"); break;
case MPU6050_CLOCK_PLL_YGYRO: Serial.println("PLL with Y axis gyroscope reference"); break;
case MPU6050_CLOCK_PLL_XGYRO: Serial.println("PLL with X axis gyroscope reference"); break;
case MPU6050_CLOCK_INTERNAL_8MHZ: Serial.println("Internal 8MHz oscillator"); break;
}

Serial.print(" * Accelerometer: ");
switch(mpu.getRange())
{
case MPU6050_RANGE_16G: Serial.println("+/- 16 g"); break;
case MPU6050_RANGE_8G: Serial.println("+/- 8 g"); break;
case MPU6050_RANGE_4G: Serial.println("+/- 4 g"); break;
case MPU6050_RANGE_2G: Serial.println("+/- 2 g"); break;
}

Serial.print(" * Accelerometer offsets: ");
Serial.print(mpu.getAccelOffsetX());
Serial.print(" / ");
Serial.print(mpu.getAccelOffsetY());
Serial.print(" / ");
Serial.println(mpu.getAccelOffsetZ());

Serial.println();
}

void loop()
{
Vector rawAccel = mpu.readRawAccel();
Vector normAccel = mpu.readNormalizeAccel();

Serial.print(" Xraw = ");
Serial.print(rawAccel.XAxis);
Serial.print(" Yraw = ");
Serial.print(rawAccel.YAxis);
Serial.print(" Zraw = ");

Serial.println(rawAccel.ZAxis);
Serial.print(" Xnorm = ");
Serial.print(normAccel.XAxis);
Serial.print(" Ynorm = ");
Serial.print(normAccel.YAxis);
Serial.print(" Znorm = ");
Serial.println(normAccel.ZAxis);

delay(1000);
}

[T94T]

Data types do have different memory sizes assigned when using ESP platform.
Quick fix:
Serial.print((int16_t)rawAccel.XAxis);
This needs to be fixed in this repository.

[d21d3q]

moreover rawAccel.XAxis is represented in memory as float, but here data from registers are being thrown to float as if it were int16_t...
What king of conversion is that?
(I was testing it on ESP and I had to cast it to int16_t. Does it work as expected on avr?)

[fabianoriccardi]

Yeah found the same problem. In original Arduino environment this makes sense, the int were 16bit, than the Vector class was intended for general calculation..