Merge pull request #59 from guihomework/F_interruptExample

Added an example for I2C with interrupts using getReadings and helpers

examples/Example19-Interrupt/Example19-Interrupt.ino

@@ -0,0 +1,142 @@
+/*
+  Using the BNO080 IMU with interrupts
+  By: Guillaume Walck
+  Date: September 23rd, 2020
+  License: This code is public domain.
+
+  This example shows how to access linear acc and quaternion data
+  through interrupts, using getReadings and multiple access.
+
+  The interrupt handler reads the available data into the library memory,
+  and maintains a flag for new data of 2 different sensor types.
+
+  Hardware Connections:
+  Attach the Qwiic Shield to your Arduino/Photon/ESP32 or other
+  Plug the sensor onto the shield
+  Serial.print it out at 9600 baud to serial monitor.
+*/
+
+#include <Wire.h>
+
+#include "SparkFun_BNO080_Arduino_Library.h" // Click here to get the library: http://librarymanager/All#SparkFun_BNO080
+BNO080 myIMU;
+
+// indicators of new data availability
+volatile byte newQuat = 0;
+volatile byte newLinAcc = 0;
+// internal copies of the IMU data
+float ax, ay, az, qx, qy, qz, qw; // (qx, qy, qz, qw = i,j,k, real)
+byte linAccuracy = 0;
+float quatRadianAccuracy = 0;
+byte quatAccuracy = 0;
+// pin used for interrupts
+byte imuINTPin = 3;
+
+void setup()
+{
+  Serial.begin(9600);
+  Serial.println();
+  Serial.println("BNO080 Read example with Interrupt handler, getReading and multiple access");
+
+  Wire.begin();
+  // imuINTPin should be input and pulled-up to be used as active-low interrupt
+  pinMode(imuINTPin, INPUT_PULLUP);
+
+  //Are you using a ESP? Check this issue for more information: https://github.com/sparkfun/SparkFun_BNO080_Arduino_Library/issues/16
+//  //=================================
+//  delay(100); //  Wait for BNO to boot
+//  // Start i2c and BNO080
+//  Wire.flush();   // Reset I2C
+//  IMU.begin(BNO080_DEFAULT_ADDRESS, Wire);
+//  Wire.begin(4, 5);
+//  Wire.setClockStretchLimit(4000);
+//  //=================================
+
+  if (myIMU.begin(BNO080_DEFAULT_ADDRESS, Wire, imuINTPin) == false)
+  {
+    Serial.println("BNO080 not detected at default I2C address. Check your jumpers and the hookup guide. Freezing...");
+    while (1);
+  }
+
+  Wire.setClock(400000); //Increase I2C data rate to 400kHz
+
+  // prepare interrupt on falling edge (= signal of new data available)
+  attachInterrupt(digitalPinToInterrupt(imuINTPin), interrupt_handler, FALLING);
+  // enable interrupts right away to not miss first reports
+  interrupts();
+
+  myIMU.enableLinearAccelerometer(50);  // m/s^2 no gravity, data update every 50 ms
+  myIMU.enableRotationVector(100); //Send data update every 100 ms
+
+  Serial.println(F("LinearAccelerometer enabled, Output in form x, y, z, accuracy, in m/s^2"));
+  Serial.println(F("Rotation vector, Output in form i, j, k, real, accuracy"));
+
+}
+
+// This function is called whenever an interrupt is detected by the arduino
+void interrupt_handler()
+{
+  // code snippet from ya-mouse
+   switch (myIMU.getReadings())
+   {
+      case SENSOR_REPORTID_LINEAR_ACCELERATION: {
+        newLinAcc = 1;
+      }
+      break;
+
+      case SENSOR_REPORTID_ROTATION_VECTOR:
+      case SENSOR_REPORTID_GAME_ROTATION_VECTOR: {
+         newQuat = 1;
+      }
+      break;
+      default:
+         // Unhandled Input Report
+         break;
+   }
+}
+
+void loop()
+{
+  Serial.println("Doing other things");
+  delay(10); //You can do many other things. Interrupt handler will retrieve latest data
+
+  // If new data on LinAcc sensor, retrieve it from the library memory
+  if(newLinAcc) {
+    myIMU.getLinAccel(ax, ay, az, linAccuracy);
+    newLinAcc = 0; // mark data as read
+    Serial.print(F("acc :"));
+    Serial.print(ax, 2);
+    Serial.print(F(","));
+    Serial.print(ay, 2);
+    Serial.print(F(","));
+    Serial.print(az, 2);
+    Serial.print(F(","));
+    Serial.print(az, 2);
+    Serial.print(F(","));
+    printAccuracyLevel(linAccuracy);
+  }
+  // If new data on Rotation Vector sensor, retrieve it from the library memory
+  if(newQuat) {
+    myIMU.getQuat(qx, qy, qz, qw, quatRadianAccuracy, quatAccuracy);
+    newQuat = 0; // mark data as read
+    Serial.print(F("quat:"));
+    Serial.print(qx, 2);
+    Serial.print(F(","));
+    Serial.print(qy, 2);
+    Serial.print(F(","));
+    Serial.print(qz, 2);
+    Serial.print(F(","));
+    Serial.print(qw, 2);
+    Serial.print(F(","));
+    printAccuracyLevel(quatAccuracy);
+  }
+}
+
+//Given an accuracy number, print what it means
+void printAccuracyLevel(byte accuracyNumber)
+{
+  if (accuracyNumber == 0) Serial.println(F("Unreliable"));
+  else if (accuracyNumber == 1) Serial.println(F("Low"));
+  else if (accuracyNumber == 2) Serial.println(F("Medium"));
+  else if (accuracyNumber == 3) Serial.println(F("High"));
+}