GroveEarbudSensor.h

00001 /* Copyright C2014 ARM, MIT License
00002  *
00003  * Author: Doug Anson (doug.anson@arm.com)
00004  *
00005  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00006  * and associated documentation files the "Software", to deal in the Software without restriction,
00007  * including without limitation the rights to use, copy, modify, merge, publish, distribute,
00008  * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in all copies or
00012  * substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00015  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00016  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00017  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00018  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00019  */
00020  
00021  #ifndef _GROVE_EARBUD_SENSOR_H_
00022  #define _GROVE_EARBUD_SENSOR_H_
00023  
00024  
00025  #include "mbed.h"
00026  
00027  // ********* BEGIN Tunables *****************
00028 
00029  #define NUM_SLOTS              6           // set higher for greater accuracy (but slower callback frequency).. 
00030  #define HEARTPULSE_DUTY        2000        // Change to follow your system's request. System returns error if the duty overtrips by 2 seconds. (in MS)
00031  
00032  #define HEARTRATE_OFF          0           // earbud sensor is offline
00033  #define HEARTRATE_MIN          10          // min heartrate
00034  #define HEARTRATE_MAX          250         // max heartrate
00035  
00036  // *********  END Tunables  *****************
00037   
00038  // Callback function signature
00039  typedef void (GroveEarbudSensorCallback)(float,void *);
00040  
00041  /**
00042  * GroveEarbudSensor 
00043  * GroveEarbudSensor a simple API to receive heartrate telemetry from the Grove Earbud Sensor
00044  *
00045  * Based upon/Credit: http://www.seeedstudio.com/wiki/Grove_-_Ear-clip_Heart_Rate_Sensor
00046  *
00047  * Example Project: http://mbed.org/users/ansond/code/grove-earbud-sensor-sample/ 
00048  *
00049  * @code
00050  *
00051  
00052  #include "mbed.h"
00053 
00054 // Blinky
00055 DigitalOut led(LED1);
00056 
00057 // Our sensor as an InterruptIn
00058 InterruptIn sensor(D0);
00059 
00060 // Grove Earbud Sensor include
00061 #include "GroveEarbudSensor.h"
00062 
00063 // callback for receiving heartrate values
00064 void heartrateCallback(float heartrate,void *data) {
00065     printf("Callback: heartrate = %.1f\r\n",heartrate);
00066 }
00067 
00068 int main()
00069 {   
00070     // announce
00071     printf("Grove Earbud Sensor Example v1.0.0\r\n");
00072     
00073     // allocate the earbud sensor
00074     printf("Allocating earbud sensor instance...\r\n");
00075     GroveEarbudSensor earbud(&sensor); 
00076     
00077     // register our callback function
00078     printf("registering callback...\r\n");
00079     earbud.registerCallback(heartrateCallback);
00080     
00081     // begin main loop
00082     printf("Beginning main loop...\r\n");
00083     while (true) {
00084         // blink... 
00085         led = !led; 
00086         wait(0.5);
00087         
00088         // we can also call directly 
00089         //printf("Direct: heartrate = %.1f\r\n",earbud.getHeartRate());
00090     }
00091 }
00092 
00093  * @endcode
00094  *
00095  */    
00096  
00097  class GroveEarbudSensor {
00098      private:
00099         RawSerial                 *m_pc;
00100         InterruptIn               *m_rx;
00101         volatile unsigned long     m_temp[NUM_SLOTS];
00102         volatile unsigned long     m_sub;
00103         volatile unsigned char     m_counter;
00104         volatile bool              m_data_effect;
00105         float                      m_heartrate;
00106         GroveEarbudSensorCallback *m_cb_fn;
00107         void                      *m_cb_data;
00108         Timer                     *m_timer;
00109         bool                       m_internal_interrupt_instance;
00110          
00111      public:
00112         /**
00113         Default constructor
00114         @param rx input InterruptIn instance
00115         @param pc input RawSerial instance for debugging (if NULL, no debugging output will occur in the library)
00116         */
00117         GroveEarbudSensor(InterruptIn *rx,RawSerial *pc = NULL);
00118         
00119         /**
00120         constructor for internalized InterruptIn usage
00121         @param rx interrupt_pin InterruptIn pin name
00122         @param pc input RawSerial instance for debugging (if NULL, no debugging output will occur in the library)
00123         */
00124         GroveEarbudSensor(PinName interrupt_pin,RawSerial *pc = NULL);
00125         
00126         /**
00127         Default destructor
00128         */
00129         virtual ~GroveEarbudSensor();
00130         
00131         /**
00132         registerCallback - Register callback function 
00133         @param cb_fn - callback function of type GroveEarbudSensorCallback
00134         @param cb_data - optional callback data to provide upon callback invocation (default - NULL)
00135         */
00136         void registerCallback(GroveEarbudSensorCallback *cb_fn,void *cb_data = NULL);
00137         
00138         /**
00139         getHeartRate - get the last sampled heartrate
00140         @return heartrate - the last calculated heartrate (may also be one of HEARTRATE_OFF, HEARTRATE_MIN, or HEARTRATE_MAX)
00141         */
00142         float getHeartRate(void);
00143         
00144         /**
00145         interrupt() - interrupt handler for our instance - not normally invoked manually
00146         */
00147         void interrupt(void);
00148         
00149     protected:
00150         void initSummationArray(void);
00151         void sumAndInvokeCallback(void);
00152  };
00153  
00154  #endif // _GROVE_EARBUD_SENSOR_H_
00155