From 076ce2bb09b0404e55795c3b687791957393215e Mon Sep 17 00:00:00 2001
From: Erik Nyquist <eknyquist@gmail.com>
Date: Tue, 24 Jan 2017 11:14:08 -0800
Subject: [PATCH] Visualize101.ino: Simplify sensor reading

CurieIMU now has dataReady() functions to check for newly available
accel/gyro data, and also readAccelerometer/GyroScaled(), which reads
then sensor and returns values scaled according to the configured range.
Using these functions in the Visualize101 example makes the source much
simpler
---
 examples/Visualize101/Visualize101.ino | 44 ++------------------------
 1 file changed, 3 insertions(+), 41 deletions(-)

diff --git a/examples/Visualize101/Visualize101.ino b/examples/Visualize101/Visualize101.ino
index bdd4500..664d571 100644
--- a/examples/Visualize101/Visualize101.ino
+++ b/examples/Visualize101/Visualize101.ino
@@ -2,7 +2,6 @@
 #include <MadgwickAHRS.h>
 
 Madgwick filter;
-unsigned long microsPerReading, microsPrevious;
 float accelScale, gyroScale;
 
 void setup() {
@@ -18,34 +17,18 @@ void setup() {
   CurieIMU.setAccelerometerRange(2);
   // Set the gyroscope range to 250 degrees/second
   CurieIMU.setGyroRange(250);
-
-  // initialize variables to pace updates to correct rate
-  microsPerReading = 1000000 / 25;
-  microsPrevious = micros();
 }
 
 void loop() {
-  int aix, aiy, aiz;
-  int gix, giy, giz;
   float ax, ay, az;
   float gx, gy, gz;
   float roll, pitch, heading;
-  unsigned long microsNow;
 
   // check if it's time to read data and update the filter
-  microsNow = micros();
-  if (microsNow - microsPrevious >= microsPerReading) {
-
-    // read raw data from CurieIMU
-    CurieIMU.readMotionSensor(aix, aiy, aiz, gix, giy, giz);
+  if (CurieIMU.dataReady()) {
 
-    // convert from raw data to gravity and degrees/second units
-    ax = convertRawAcceleration(aix);
-    ay = convertRawAcceleration(aiy);
-    az = convertRawAcceleration(aiz);
-    gx = convertRawGyro(gix);
-    gy = convertRawGyro(giy);
-    gz = convertRawGyro(giz);
+    // read scaled data from CurieIMU
+    CurieIMU.readMotionSensorScaled(ax, ay, az, gx, gy, gz);
 
     // update the filter, which computes orientation
     filter.updateIMU(gx, gy, gz, ax, ay, az);
@@ -60,26 +43,5 @@ void loop() {
     Serial.print(pitch);
     Serial.print(" ");
     Serial.println(roll);
-
-    // increment previous time, so we keep proper pace
-    microsPrevious = microsPrevious + microsPerReading;
   }
 }
-
-float convertRawAcceleration(int aRaw) {
-  // since we are using 2G range
-  // -2g maps to a raw value of -32768
-  // +2g maps to a raw value of 32767
-  
-  float a = (aRaw * 2.0) / 32768.0;
-  return a;
-}
-
-float convertRawGyro(int gRaw) {
-  // since we are using 250 degrees/seconds range
-  // -250 maps to a raw value of -32768
-  // +250 maps to a raw value of 32767
-  
-  float g = (gRaw * 250.0) / 32768.0;
-  return g;
-}