Clark Scheff / Ping

Library for interfacing with the Parallax Ping))) sensor.

Dependencies:   FPointer

ping.h@4:ddffe9339bb1, 2014-07-28 (annotated)

Committer:
d34d
Date:
Mon Jul 28 00:17:57 2014 +0000
Revision:
4:ddffe9339bb1
Parent:
3:0c337c262d84
Child:
5:cbe07c09c64c
Make getDistanceXX methods static.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
d34d 0:99ee7c741e9d 1 #ifndef PING_H
d34d 0:99ee7c741e9d 2 #define PING_H
d34d 0:99ee7c741e9d 3
d34d 0:99ee7c741e9d 4 #include "mbed.h"
d34d 0:99ee7c741e9d 5 #include "FPointer.h"
d34d 0:99ee7c741e9d 6
d34d 3:0c337c262d84 7 #define MEASUREMENT_DELAY_US 200
d34d 3:0c337c262d84 8 #define SPEED_OF_SOUND_CM_PER_US 0.034029
d34d 3:0c337c262d84 9 #define SPEED_OF_SOUND_IN_PER_US 0.0133972441
d34d 1:72fbcb01291d 10
d34d 0:99ee7c741e9d 11 /**
d34d 0:99ee7c741e9d 12 * Class for interfacing with the Parallax Ping))) Ultrasonic Sensor
d34d 0:99ee7c741e9d 13 *
d34d 0:99ee7c741e9d 14 * See the Ping)) documentation for more information.
d34d 0:99ee7c741e9d 15 * http://www.parallax.com/sites/default/files/downloads/28015-PING-Documentation-v1.6.pdf
d34d 0:99ee7c741e9d 16 */
d34d 0:99ee7c741e9d 17 class Ping {
d34d 0:99ee7c741e9d 18 public:
d34d 0:99ee7c741e9d 19 /**
d34d 0:99ee7c741e9d 20 * @param pin Digital I/O pin used for communicating with the Ping)))
d34d 0:99ee7c741e9d 21 */
d34d 0:99ee7c741e9d 22 Ping(PinName pin);
d34d 0:99ee7c741e9d 23
d34d 0:99ee7c741e9d 24 /**
d34d 0:99ee7c741e9d 25 * Starts a one shot reading.
d34d 0:99ee7c741e9d 26 *
d34d 0:99ee7c741e9d 27 * @return True if the reading was successfuly started, false if not.
d34d 0:99ee7c741e9d 28 */
d34d 0:99ee7c741e9d 29 bool startReading();
d34d 0:99ee7c741e9d 30
d34d 0:99ee7c741e9d 31 /**
d34d 0:99ee7c741e9d 32 * Starts a reading.
d34d 0:99ee7c741e9d 33 *
d34d 0:99ee7c741e9d 34 * @param continuous Continuous readings if true, one-shot if false.
d34d 0:99ee7c741e9d 35 * @return True if the reading was successfuly started, false if not.
d34d 0:99ee7c741e9d 36 */
d34d 0:99ee7c741e9d 37 bool startReading(bool continuous);
d34d 0:99ee7c741e9d 38
d34d 0:99ee7c741e9d 39 /**
d34d 0:99ee7c741e9d 40 * Returns whether the sensor is busy getting a reading
d34d 0:99ee7c741e9d 41 *
d34d 0:99ee7c741e9d 42 * @return True if busy, false if not.
d34d 0:99ee7c741e9d 43 */
d34d 0:99ee7c741e9d 44 bool isBusy() { return mBusy; }
d34d 0:99ee7c741e9d 45
d34d 0:99ee7c741e9d 46 /**
d34d 0:99ee7c741e9d 47 * Returns whether the valid reading is available
d34d 0:99ee7c741e9d 48 *
d34d 0:99ee7c741e9d 49 * @return True if valid, false if not.
d34d 0:99ee7c741e9d 50 */
d34d 0:99ee7c741e9d 51 bool isValid() { return mValid; }
d34d 0:99ee7c741e9d 52
d34d 0:99ee7c741e9d 53 /**
d34d 0:99ee7c741e9d 54 * Returns the raw reading from the sensor.
d34d 0:99ee7c741e9d 55 *
d34d 0:99ee7c741e9d 56 * @return The time in uS that the sound travelled from the sensor to an object.
d34d 0:99ee7c741e9d 57 */
d34d 0:99ee7c741e9d 58 uint32_t getRawReading() { return mRawReading; }
d34d 0:99ee7c741e9d 59
d34d 0:99ee7c741e9d 60 /**
d34d 3:0c337c262d84 61 * Gets the distance sound can travel, in centimeters, for a given time in uS.
d34d 3:0c337c262d84 62 *
d34d 3:0c337c262d84 63 * @param time_us Time traveled in microseconds.
d34d 3:0c337c262d84 64 * @return The distance traveled in centimeters.
d34d 3:0c337c262d84 65 */
d34d 4:ddffe9339bb1 66 static float getDistanceCm(uint32_t time_us) { return time_us * SPEED_OF_SOUND_CM_PER_US; }
d34d 3:0c337c262d84 67
d34d 3:0c337c262d84 68 /**
d34d 3:0c337c262d84 69 * Gets the distance sound can travel, in inches, for a given time in uS.
d34d 3:0c337c262d84 70 *
d34d 3:0c337c262d84 71 * @param time_us Time traveled in microseconds.
d34d 3:0c337c262d84 72 * @return The distance traveled in inches.
d34d 3:0c337c262d84 73 */
d34d 4:ddffe9339bb1 74 static float getDistanceIn(uint32_t time_us) { return time_us * SPEED_OF_SOUND_IN_PER_US; }
d34d 3:0c337c262d84 75
d34d 3:0c337c262d84 76 /**
d34d 0:99ee7c741e9d 77 * Attach a callback function that will be called when a valid reading is available.
d34d 0:99ee7c741e9d 78 *
d34d 0:99ee7c741e9d 79 * @param function Function pointer for callback.
d34d 0:99ee7c741e9d 80 */
d34d 0:99ee7c741e9d 81 void attach(uint32_t (*function)(uint32_t) = 0) { mCallback.attach(function); }
d34d 0:99ee7c741e9d 82
d34d 0:99ee7c741e9d 83 /**
d34d 0:99ee7c741e9d 84 * Attach a class method that will be called when a valid reading is available.
d34d 0:99ee7c741e9d 85 *
d34d 0:99ee7c741e9d 86 * @param item Class object that contains the method to call.
d34d 0:99ee7c741e9d 87 * @param method Method to call.
d34d 0:99ee7c741e9d 88 */
d34d 0:99ee7c741e9d 89 template<class T>
d34d 0:99ee7c741e9d 90 void attach(T* item, uint32_t (T::*method)(uint32_t)) { mCallback.attach(item, method); }
d34d 0:99ee7c741e9d 91
d34d 0:99ee7c741e9d 92 private:
d34d 0:99ee7c741e9d 93 DigitalInOut mSignalIo;
d34d 0:99ee7c741e9d 94 InterruptIn mEvent;
d34d 0:99ee7c741e9d 95
d34d 0:99ee7c741e9d 96 bool mBusy;
d34d 0:99ee7c741e9d 97 bool mValid;
d34d 0:99ee7c741e9d 98 bool mContinuous;
d34d 0:99ee7c741e9d 99
d34d 0:99ee7c741e9d 100 Timer mTimer;
d34d 1:72fbcb01291d 101 Ticker mMeasureDelayTicker;
d34d 0:99ee7c741e9d 102
d34d 0:99ee7c741e9d 103 uint32_t mRawReading;
d34d 0:99ee7c741e9d 104
d34d 0:99ee7c741e9d 105 FPointer mCallback;
d34d 0:99ee7c741e9d 106
d34d 0:99ee7c741e9d 107 void start();
d34d 0:99ee7c741e9d 108 void stop();
d34d 1:72fbcb01291d 109 void nextMeasurement();
d34d 0:99ee7c741e9d 110 };
d34d 0:99ee7c741e9d 111
d34d 0:99ee7c741e9d 112 #endif