imu: minor clean-ups

- removed some dead code
- added/corrected some code comments

Signed-off-by: Dan O'Donovan <dan@emutex.com>

Author: Dan-Lightsource

libraries/CurieImu/src/BMI160.cpp

@@ -31,8 +31,6 @@ THE SOFTWARE.
 */
 #include "BMI160.h"
 
-#define ACCEL_CONVERT_CONST 9800
-
 #define BMI160_CHIP_ID 0xD1
 
 #define BMI160_ACCEL_POWERUP_DELAY_MS 10
@@ -42,10 +40,6 @@ THE SOFTWARE.
 #define BMI160_SIGN_EXTEND(val, from) \
     (((val) & (1 << ((from) - 1))) ? (val | (((1 << (1 + (sizeof(val) << 3) - (from))) - 1) << (from))) : val)
 
-//static uint8_t acc_sensitivity_shift = BMI160_SENSITIVITY_ACCEL_8G_SHIFT;
-//static uint16_t gyro_convert_numerator = 305;
-//static uint16_t gyro_convert_denominator = 10;
-
 /******************************************************************************/
 
 uint8_t BMI160Class::reg_read (uint8_t reg)
@@ -206,6 +200,7 @@ uint8_t BMI160Class::getAccelRate() {
                          BMI160_ACCEL_RATE_SEL_BIT,
                          BMI160_ACCEL_RATE_SEL_LEN);
 }
+
 /** Set accelerometer output data rate.
  * @param rate New output data rate
  * @see getGyroRate()
@@ -252,6 +247,7 @@ uint8_t BMI160Class::getGyroDLPFMode() {
                          BMI160_GYRO_DLPF_SEL_BIT,
                          BMI160_GYRO_DLPF_SEL_LEN);
 }
+
 /** Set gyroscope digital low-pass filter configuration.
  * @param mode New DLFP configuration setting
  * @see getGyroDLPFMode()
@@ -296,6 +292,7 @@ uint8_t BMI160Class::getAccelDLPFMode() {
                          BMI160_ACCEL_DLPF_SEL_BIT,
                          BMI160_ACCEL_DLPF_SEL_LEN);
 }
+
 /** Set accelerometer digital low-pass filter configuration.
  * @param mode New DLFP configuration setting
  * @see getAccelDLPFMode()
@@ -306,7 +303,6 @@ void BMI160Class::setAccelDLPFMode(uint8_t mode) {
                           BMI160_ACCEL_DLPF_SEL_LEN);
 }
 
-
 /** Get full-scale gyroscope range.
  * The gyr_range parameter allows setting the full-scale range of the gyro sensors,
  * as described in the table below.
@@ -975,6 +971,7 @@ uint8_t BMI160Class::getMotionDetectionDuration() {
                              BMI160_ANYMOTION_DUR_BIT,
                              BMI160_ANYMOTION_DUR_LEN);
 }
+
 /** Set motion detection event duration threshold.
  * @param duration New motion detection duration threshold value (#samples [1-4])
  * @see getMotionDetectionDuration()
@@ -1019,6 +1016,7 @@ void BMI160Class::setMotionDetectionDuration(uint8_t samples) {
 uint8_t BMI160Class::getZeroMotionDetectionThreshold() {
     return reg_read(BMI160_RA_INT_MOTION_2);
 }
+
 /** Set zero motion detection event acceleration threshold.
  * @param threshold New zero motion detection acceleration threshold value
  * @see getZeroMotionDetectionThreshold()
@@ -1676,7 +1674,7 @@ uint8_t BMI160Class::getIntStatus3() {
  *
  * @return Current interrupt status
  * @see BMI160_RA_INT_STATUS_1
- * @see BMI160_HIGH_G_INT_BIT
+ * @see BMI160_LOW_G_INT_BIT
  */
 bool BMI160Class::getIntFreefallStatus() {
     return !!(reg_read_bits(BMI160_RA_INT_STATUS_1,
@@ -2212,14 +2210,6 @@ void BMI160Class::getAcceleration(int16_t* x, int16_t* y, int16_t* z) {
     *x = (((int16_t)buffer[1]) << 8) | buffer[0];
     *y = (((int16_t)buffer[3]) << 8) | buffer[2];
     *z = (((int16_t)buffer[5]) << 8) | buffer[4];
-
-/* TODO - figure out if the conversion below is needed here */
-#if 0
-    /* convert accel data */
-    data_accel.x = (int16_t) ((data_accel.x * ACCEL_CONVERT_CONST) >> acc_sensitivity_shift);
-    data_accel.y = (int16_t) ((data_accel.y * ACCEL_CONVERT_CONST) >> acc_sensitivity_shift);
-    data_accel.z = (int16_t) ((data_accel.z * ACCEL_CONVERT_CONST) >> acc_sensitivity_shift);
-#endif
 }
 
 /** Get X-axis accelerometer reading.
@@ -2317,13 +2307,6 @@ void BMI160Class::getRotation(int16_t* x, int16_t* y, int16_t* z) {
     *x = (((int16_t)buffer[1]) << 8) | buffer[0];
     *y = (((int16_t)buffer[3]) << 8) | buffer[2];
     *z = (((int16_t)buffer[5]) << 8) | buffer[4];
-
-#if 0
-    /* convert gyro data */
-    data_gyro.x = (data_gyro.x * gyro_convert_numerator) / gyro_convert_denominator;
-    data_gyro.y = (data_gyro.y * gyro_convert_numerator) / gyro_convert_denominator;
-    data_gyro.z = (data_gyro.z * gyro_convert_numerator) / gyro_convert_denominator;
-#endif
 }
 
 /** Get X-axis gyroscope reading.
@@ -2359,8 +2342,6 @@ int16_t BMI160Class::getRotationZ() {
     return (((int16_t)buffer[1]) << 8) | buffer[0];
 }
 
-
-
 /** Read a BMI160 register directly.
  * @param reg register address
  * @return 8-bit register value

libraries/CurieImu/src/BMI160.h

@@ -361,26 +361,6 @@ class BMI160Class {
         uint8_t getFullScaleAccelRange();
         void setFullScaleAccelRange(uint8_t range);
 
-
-#if 0
-		// SELF_TEST registers
-		uint8_t getAccelXSelfTestFactoryTrim();
-		uint8_t getAccelYSelfTestFactoryTrim();
-		uint8_t getAccelZSelfTestFactoryTrim();
-
-		uint8_t getGyroXSelfTestFactoryTrim();
-		uint8_t getGyroYSelfTestFactoryTrim();
-		uint8_t getGyroZSelfTestFactoryTrim();
-		
-        // ACCEL_CONFIG register
-        bool getAccelXSelfTest();
-        void setAccelXSelfTest(bool enabled);
-        bool getAccelYSelfTest();
-        void setAccelYSelfTest(bool enabled);
-        bool getAccelZSelfTest();
-        void setAccelZSelfTest(bool enabled);
-#endif
-
         void autoCalibrateGyroOffset();
         bool getGyroOffsetEnabled();
         void setGyroOffsetEnabled(bool enabled);
@@ -550,7 +530,6 @@ class BMI160Class {
     protected:
         virtual int serial_buffer_transfer(uint8_t *buf, unsigned tx_cnt, unsigned rx_cnt);
 
-
     private:
         uint8_t reg_read (uint8_t reg);
         void reg_write(uint8_t reg, uint8_t data);

libraries/CurieImu/src/CurieImu.h

@@ -1,4 +1,6 @@
 /*
+ * BMI160 accelerometer/gyroscope library for Intel(R) Curie(TM) devices.
+ *
  * Copyright (c) 2015 Intel Corporation.  All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ -22,6 +24,16 @@
 
 #include "BMI160.h"
 
+/* Note that this CurieImuClass class inherits methods from the BMI160Class which
+ * is defined in BMI160.h.  BMI160Class provides methods for configuring and
+ * accessing features of the BMI160 IMU device.  This CurieImuClass extends that
+ * class with implementation of details specific to the integration of the BMI160
+ * device on the Intel Curie module, such as the serial communication interface
+ * and interrupt signalling.
+ *
+ * Please refer to the respective .cpp files for documentation on each of the
+ * methods provided by these classes.
+ */
 class CurieImuClass : public BMI160Class {
     friend void bmi160_pin1_isr(void);