MPU

.gitignore

@@ -1 +1,2 @@
 .DS_Store
+.vscode

src/buoy_wemos/buoy_wemos.ino

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+#include "mpu/mpu.h"
+
+void setup() {
+	Serial.begin(9600);
+	Wire.begin();
+	delay(2000);
+
+	initialize_mpu();
+	Serial.println("done.");
+	delay(2000);
+}
+
+void loop() {
+  xyzFloat gValue = mpu.getGValues();
+  xyzFloat gyr = mpu.getGyrValues();
+  float temp = mpu.getTemperature();
+  float resultantG = mpu.getResultantG(gValue);
+
+  Serial.print("acc [g] x,y,z,g:\t\t");
+  Serial.print(gValue.x);
+  Serial.print("\t\t");
+  Serial.print(gValue.y);
+  Serial.print("\t\t");
+  Serial.print(gValue.z);
+  Serial.print("\t\t");
+  Serial.println(resultantG);
+
+  Serial.print("gyro [deg/s] x,y,z:\t\t");
+  Serial.print(gyr.x);
+  Serial.print("\t\t");
+  Serial.print(gyr.y);
+  Serial.print("\t\t");
+  Serial.println(gyr.z);
+
+  Serial.print("Temperature [°C]: ");
+  Serial.println(temp);
+
+  Serial.println("********************************************");
+
+  delay(1000);
+}

src/buoy_wemos/mpu/mpu.h

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+#include <MPU6500_WE.h>
+#include <Wire.h>
+#define MPU6500_ADDR 0x68
+
+MPU6500_WE mpu = MPU6500_WE(MPU6500_ADDR);
+
+void initialize_mpu() {
+	// calibrates the MPU and initializes the I2C connection
+	// based on: https://github.com/wollewald/MPU9250_WE/blob/main/examples/MPU6500_all_data/MPU6500_all_data.ino
+
+	if(!mpu.init()){
+		Serial.println("no response from MPU (yet)");
+	}else{
+		Serial.println("MPU is connected");
+	}
+
+	/* The slope of the curve of acceleration vs measured values fits quite well to the theoretical 
+	* values, e.g. 16384 units/g in the +/- 2g range. But the starting point, if you position the 
+	* MPU6500 flat, is not necessarily 0g/0g/1g for x/y/z. The autoOffset function measures offset 
+	* values. It assumes your MPU6500 is positioned flat with its x,y-plane. The more you deviate 
+	* from this, the less accurate will be your results.
+	* The function also measures the offset of the gyroscope data. The gyroscope offset does not   
+	* depend on the positioning.
+	* This function needs to be called at the beginning since it can overwrite your settings!
+	*/
+	Serial.println("Position the device flat and don't move it - calibrating...");
+	delay(1000);
+	mpu.autoOffsets();
+	Serial.println("Done!");
+
+	/*  This is a more accurate method for calibration. You have to determine the minimum and maximum 
+	*  raw acceleration values of the axes determined in the range +/- 2 g. 
+	*  You call the function as follows: setAccOffsets(xMin,xMax,yMin,yMax,zMin,zMax);
+	*  Use either autoOffset or setAccOffsets, not both.
+	*/
+	//mpu.setAccOffsets(-14240.0, 18220.0, -17280.0, 15590.0, -20930.0, 12080.0);
+
+	/*  The gyroscope data is not zero, even if you don't move the MPU6500. 
+	*  To start at zero, you can apply offset values. These are the gyroscope raw values you obtain
+	*  using the +/- 250 degrees/s range. 
+	*  Use either autoOffset or setGyrOffsets, not both.
+	*/
+	//mpu.setGyrOffsets(45.0, 145.0, -105.0);
+
+	/*  You can enable or disable the digital low pass filter (DLPF). If you disable the DLPF, you 
+	*  need to select the bandwdith, which can be either 8800 or 3600 Hz. 8800 Hz has a shorter delay,
+	*  but higher noise level. If DLPF is disabled, the output rate is 32 kHz.
+	*  MPU6500_BW_WO_DLPF_3600 
+	*  MPU6500_BW_WO_DLPF_8800
+	*/
+	mpu.enableGyrDLPF();
+	//mpu.disableGyrDLPF(MPU6500_BW_WO_DLPF_8800); // bandwdith without DLPF
+
+	/*  Digital Low Pass Filter for the gyroscope must be enabled to choose the level. 
+	*  MPU6500_DPLF_0, MPU6500_DPLF_2, ...... MPU6500_DPLF_7 
+	*  
+	*  DLPF    Bandwidth [Hz]   Delay [ms]   Output Rate [kHz]
+	*    0         250            0.97             8
+	*    1         184            2.9              1
+	*    2          92            3.9              1
+	*    3          41            5.9              1
+	*    4          20            9.9              1
+	*    5          10           17.85             1
+	*    6           5           33.48             1
+	*    7        3600            0.17             8
+	*    
+	*    You achieve lowest noise using level 6  
+	*/
+	mpu.setGyrDLPF(MPU6500_DLPF_6);
+
+	/*  Sample rate divider divides the output rate of the gyroscope and accelerometer.
+	*  Sample rate = Internal sample rate / (1 + divider) 
+	*  It can only be applied if the corresponding DLPF is enabled and 0<DLPF<7!
+	*  Divider is a number 0...255
+	*/
+	mpu.setSampleRateDivider(5);
+
+	/*  MPU6500_GYRO_RANGE_250       250 degrees per second (default)
+	*  MPU6500_GYRO_RANGE_500       500 degrees per second
+	*  MPU6500_GYRO_RANGE_1000     1000 degrees per second
+	*  MPU6500_GYRO_RANGE_2000     2000 degrees per second
+	*/
+	mpu.setGyrRange(MPU6500_GYRO_RANGE_250);
+
+	/*  MPU6500_ACC_RANGE_2G      2 g   (default)
+	*  MPU6500_ACC_RANGE_4G      4 g
+	*  MPU6500_ACC_RANGE_8G      8 g   
+	*  MPU6500_ACC_RANGE_16G    16 g
+	*/
+	mpu.setAccRange(MPU6500_ACC_RANGE_2G);
+
+	/*  Enable/disable the digital low pass filter for the accelerometer 
+	*  If disabled the bandwidth is 1.13 kHz, delay is 0.75 ms, output rate is 4 kHz
+	*/
+	mpu.enableAccDLPF(true);
+
+	/*  Digital low pass filter (DLPF) for the accelerometer, if enabled 
+	*  MPU6500_DPLF_0, MPU6500_DPLF_2, ...... MPU6500_DPLF_7 
+	*   DLPF     Bandwidth [Hz]      Delay [ms]    Output rate [kHz]
+	*     0           460               1.94           1
+	*     1           184               5.80           1
+	*     2            92               7.80           1
+	*     3            41              11.80           1
+	*     4            20              19.80           1
+	*     5            10              35.70           1
+	*     6             5              66.96           1
+	*     7           460               1.94           1
+	*/
+	mpu.setAccDLPF(MPU6500_DLPF_6);
+
+	/* You can enable or disable the axes for gyroscope and/or accelerometer measurements.
+	* By default all axes are enabled. Parameters are:  
+	* MPU6500_ENABLE_XYZ  //all axes are enabled (default)
+	* MPU6500_ENABLE_XY0  // X, Y enabled, Z disabled
+	* MPU6500_ENABLE_X0Z   
+	* MPU6500_ENABLE_X00
+	* MPU6500_ENABLE_0YZ
+	* MPU6500_ENABLE_0Y0
+	* MPU6500_ENABLE_00Z
+	* MPU6500_ENABLE_000  // all axes disabled
+	*/
+	//mpu.enableAccAxes(MPU6500_ENABLE_XYZ);
+	//mpu.enableGyrAxes(MPU6500_ENABLE_XYZ);
+}
+
+/*
+	EXAMPLE
+
+void setup() {
+	Serial.begin(9600);
+	Wire.begin();
+	delay(2000);
+
+	initialize_mpu();
+	Serial.println("done.");
+	delay(2000);
+}
+
+void loop() {
+  xyzFloat gValue = mpu.getGValues();
+  xyzFloat gyr = mpu.getGyrValues();
+  float temp = mpu.getTemperature();
+  float resultantG = mpu.getResultantG(gValue);
+
+  Serial.print("acc [g] x,y,z,g:\t\t");
+  Serial.print(gValue.x);
+  Serial.print("\t\t");
+  Serial.print(gValue.y);
+  Serial.print("\t\t");
+  Serial.print(gValue.z);
+  Serial.print("\t\t");
+  Serial.println(resultantG);
+
+  Serial.print("gyro [deg/s] x,y,z:\t\t");
+  Serial.print(gyr.x);
+  Serial.print("\t\t");
+  Serial.print(gyr.y);
+  Serial.print("\t\t");
+  Serial.println(gyr.z);
+
+  Serial.print("Temperature [°C]: ");
+  Serial.println(temp);
+
+  Serial.println("********************************************");
+
+  delay(1000);
+}
+
+*/

src/buoy_wemos/mpu/testing/connection_check/connection_check.ino

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+#include "MPU9250.h"
+
+uint8_t addrs[7] = {0};
+uint8_t device_count = 0;
+
+template <typename WireType = TwoWire>
+void scan_mpu(WireType& wire = Wire) {
+    Serial.println("Searching for i2c devices...");
+    device_count = 0;
+    for (uint8_t i = 0x68; i < 0x70; ++i) {
+        wire.beginTransmission(i);
+        if (wire.endTransmission() == 0) {
+            addrs[device_count++] = i;
+            delay(10);
+        }
+    }
+    Serial.print("Found ");
+    Serial.print(device_count, DEC);
+    Serial.println(" I2C devices");
+
+    Serial.print("I2C addresses are: ");
+    for (uint8_t i = 0; i < device_count; ++i) {
+        Serial.print("0x");
+        Serial.print(addrs[i], HEX);
+        Serial.print(" ");
+    }
+    Serial.println();
+}
+
+template <typename WireType = TwoWire>
+uint8_t readByte(uint8_t address, uint8_t subAddress, WireType& wire = Wire) {
+    uint8_t data = 0;
+    wire.beginTransmission(address);
+    wire.write(subAddress);
+    wire.endTransmission(false);
+    wire.requestFrom(address, (size_t)1);
+    if (wire.available()) data = wire.read();
+    return data;
+}
+
+void setup() {
+    // Serial.begin(115200);
+    Serial.begin(9600);
+    Serial.flush();
+    Wire.begin();
+    delay(2000);
+
+    scan_mpu();
+
+    if (device_count == 0) {
+        Serial.println("No device found on I2C bus. Please check your hardware connection");
+        while (1)
+            ;
+    }
+
+    // check WHO_AM_I address of MPU
+    for (uint8_t i = 0; i < device_count; ++i) {
+        Serial.print("I2C address 0x");
+        Serial.print(addrs[i], HEX);
+        byte ca = readByte(addrs[i], WHO_AM_I_MPU9250);
+        if (ca == MPU9250_WHOAMI_DEFAULT_VALUE) {
+            Serial.println(" is MPU9250 and ready to use");
+        } else if (ca == MPU9255_WHOAMI_DEFAULT_VALUE) {
+            Serial.println(" is MPU9255 and ready to use");
+        } else if (ca == MPU6500_WHOAMI_DEFAULT_VALUE) {
+            Serial.println(" is MPU6500 and ready to use");
+        } else {
+            Serial.println(" is not MPU series");
+            Serial.print("WHO_AM_I is ");
+            Serial.println(ca, HEX);
+            Serial.println("Please use correct device");
+        }
+        static constexpr uint8_t AK8963_ADDRESS {0x0C};  //  Address of magnetometer
+        static constexpr uint8_t AK8963_WHOAMI_DEFAULT_VALUE {0x48};
+        byte cb = readByte(AK8963_ADDRESS, AK8963_WHO_AM_I);
+        if (cb == AK8963_WHOAMI_DEFAULT_VALUE) {
+            Serial.print("AK8963 (Magnetometer) is ready to use");
+        } else {
+            Serial.print("AK8963 (Magnetometer) was not found");
+        }
+    }
+}
+
+void loop() {
+}

src/buoy_wemos/mpu/testing/test1/test1.ino

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+#include <Arduino.h>
+#include <Wire.h>
+#include <MPU9250.h>
+
+MPU9250 mpu; // You can also use MPU9255 as is
+void print(char* msg) {
+    Serial.println(msg);
+}
+
+void setup() {
+    print("booting");
+    Serial.begin(9600);
+    Wire.begin();
+    print("wire open");
+
+    delay(2000);
+
+    print("calibrating mpu");
+    mpu.setup(0x68);  // change to your own address
+    // mpu.calibrateAccelGyro();
+    // mpu.calibrateMag();
+    print("setup done.");
+}
+
+// the loop function runs over and over again forever
+void loop() {
+    print("looping");
+    scan_i2c();
+
+    // if (mpu.update()) {
+    //     Serial.print(mpu.getYaw()); Serial.print(", ");
+    //     Serial.print(mpu.getPitch()); Serial.print(", ");
+    //     Serial.println(mpu.getRoll());
+    // }
+    delay(1000);
+}
+
+int* scan_i2c() {
+    int nDevices = 0;
+    int* devices = (int*)malloc(128 * sizeof(int));
+    Serial.println("Scanning...");
+    for (int i = 1; i < 127; i++) {
+        Wire.beginTransmission(i);
+        if (Wire.endTransmission() == 0) {
+            Serial.print("I2C device found at address 0x");
+            if (i < 16) {
+                Serial.print("0");
+            }
+            Serial.print(i, HEX);
+            Serial.println(" !");
+            devices[nDevices] = i;
+            nDevices++;
+        }
+    }
+    if (nDevices == 0) {
+        Serial.println("No I2C devices found");
+    } else {
+        Serial.println("done");
+    }
+    if (nDevices < 128) {
+        devices[nDevices] = -1;  // mark end of array
+    }
+    return devices;
+}