Jochen Krapf / Pulses

Measurement of low frequencys based on timing between pulses

Dependents:   Energy_Meter_S0_Example

Pulses.h@1:6eb686d7d16a, 2012-11-08 (annotated)

Committer:
jocis
Date:
Thu Nov 08 07:25:41 2012 +0000
Revision:
1:6eb686d7d16a
Parent:
0:ef402fb370c5
Child:
2:fc21262db17a
added min, max; added function get()

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jocis 0:ef402fb370c5 1 /*
jocis 0:ef402fb370c5 2 * @author Jochen Krapf
jocis 0:ef402fb370c5 3 *
jocis 0:ef402fb370c5 4 * @section LICENSE
jocis 0:ef402fb370c5 5 *
jocis 0:ef402fb370c5 6 * Copyright (c) 2012 Jochen Krapf, MIT License
jocis 0:ef402fb370c5 7 *
jocis 0:ef402fb370c5 8 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
jocis 0:ef402fb370c5 9 * and associated documentation files (the "Software"), to deal in the Software without restriction,
jocis 0:ef402fb370c5 10 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
jocis 0:ef402fb370c5 11 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
jocis 0:ef402fb370c5 12 * furnished to do so, subject to the following conditions:
jocis 0:ef402fb370c5 13 *
jocis 0:ef402fb370c5 14 * The above copyright notice and this permission notice shall be included in all copies or
jocis 0:ef402fb370c5 15 * substantial portions of the Software.
jocis 0:ef402fb370c5 16 *
jocis 0:ef402fb370c5 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
jocis 0:ef402fb370c5 18 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
jocis 0:ef402fb370c5 19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
jocis 0:ef402fb370c5 20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
jocis 0:ef402fb370c5 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
jocis 0:ef402fb370c5 22 *
jocis 0:ef402fb370c5 23 * @section DESCRIPTION
jocis 1:6eb686d7d16a 24 * mbed Pulses Library, for measurement of low frequencys based on timing between pulses
jocis 0:ef402fb370c5 25 *
jocis 0:ef402fb370c5 26 * Use cases:
jocis 0:ef402fb370c5 27 * - Motor rotations (rpm)
jocis 0:ef402fb370c5 28 * - Energy meter with SO interface
jocis 0:ef402fb370c5 29 *
jocis 0:ef402fb370c5 30 * Example:
jocis 0:ef402fb370c5 31 *
jocis 0:ef402fb370c5 32 * @code
jocis 0:ef402fb370c5 33 #include "mbed.h"
jocis 0:ef402fb370c5 34 #include "Pulses.h"
jocis 0:ef402fb370c5 35
jocis 0:ef402fb370c5 36 Pulses pulses(p8, Pulses::FALL);
jocis 0:ef402fb370c5 37 Serial pc(USBTX, USBRX); // tx, rx
jocis 0:ef402fb370c5 38
jocis 0:ef402fb370c5 39 int main() {
jocis 0:ef402fb370c5 40 // choose on of the following unit scales
jocis 0:ef402fb370c5 41 pulses.setFactor(1.0f); // Hz
jocis 0:ef402fb370c5 42 pulses.setFactor(60.0f); // rpm
jocis 0:ef402fb370c5 43 pulses.setFactor(3600.0f/2000.0f); // kWh; energy meter with SO interface - 2000 pulses per kWh
jocis 0:ef402fb370c5 44
jocis 0:ef402fb370c5 45 while(1) {
jocis 0:ef402fb370c5 46 pc.printf ( "Pulses: counter=%d act=%.3f average=%.3f\r\n",
jocis 0:ef402fb370c5 47 pulses.getCounter(),
jocis 0:ef402fb370c5 48 pulses.getAct(),
jocis 0:ef402fb370c5 49 pulses.getAverage() );
jocis 0:ef402fb370c5 50
jocis 0:ef402fb370c5 51 wait(3.14);
jocis 0:ef402fb370c5 52 }
jocis 0:ef402fb370c5 53 }
jocis 0:ef402fb370c5 54 * @endcode
jocis 0:ef402fb370c5 55 *
jocis 0:ef402fb370c5 56 */
jocis 0:ef402fb370c5 57
jocis 0:ef402fb370c5 58 #ifndef MBED_PULSES_H
jocis 0:ef402fb370c5 59 #define MBED_PULSES_H
jocis 0:ef402fb370c5 60
jocis 0:ef402fb370c5 61 #include "mbed.h"
jocis 0:ef402fb370c5 62
jocis 0:ef402fb370c5 63 class TimerDiff : public Timer {
jocis 0:ef402fb370c5 64 public:
jocis 0:ef402fb370c5 65 TimerDiff(const char *name = NULL) : Timer(name) {
jocis 0:ef402fb370c5 66 reset();
jocis 0:ef402fb370c5 67 start();
jocis 0:ef402fb370c5 68 _last = 0;
jocis 0:ef402fb370c5 69 };
jocis 0:ef402fb370c5 70
jocis 0:ef402fb370c5 71 unsigned int readDiff_us() {
jocis 0:ef402fb370c5 72 unsigned int act = read_us();
jocis 0:ef402fb370c5 73 unsigned int diff;
jocis 0:ef402fb370c5 74
jocis 0:ef402fb370c5 75 if ( act < _last ) // overflow
jocis 0:ef402fb370c5 76 diff = act - _last;
jocis 0:ef402fb370c5 77 else
jocis 0:ef402fb370c5 78 diff = act - _last;
jocis 0:ef402fb370c5 79 _last = act;
jocis 0:ef402fb370c5 80 return diff;
jocis 0:ef402fb370c5 81 }
jocis 0:ef402fb370c5 82
jocis 0:ef402fb370c5 83 float readDiff() {
jocis 0:ef402fb370c5 84 return (float)readDiff_us() * 0.000001;
jocis 0:ef402fb370c5 85 }
jocis 0:ef402fb370c5 86
jocis 0:ef402fb370c5 87 protected:
jocis 0:ef402fb370c5 88 unsigned int _last;
jocis 0:ef402fb370c5 89 };
jocis 0:ef402fb370c5 90
jocis 0:ef402fb370c5 91
jocis 0:ef402fb370c5 92 /** A class to calculate frequencys based on timing between pulses. Pulse-frequency can be about or slower than loop/aquisition time
jocis 0:ef402fb370c5 93 *
jocis 0:ef402fb370c5 94 */
jocis 0:ef402fb370c5 95 class Pulses {
jocis 0:ef402fb370c5 96 public:
jocis 0:ef402fb370c5 97
jocis 0:ef402fb370c5 98 /** Pulses type format */
jocis 0:ef402fb370c5 99 enum PulseType {
jocis 0:ef402fb370c5 100 RISE=1,
jocis 0:ef402fb370c5 101 FALL=2,
jocis 0:ef402fb370c5 102 CHANGE=3
jocis 0:ef402fb370c5 103 };
jocis 0:ef402fb370c5 104
jocis 0:ef402fb370c5 105 /** constructor of Pulses object
jocis 0:ef402fb370c5 106 *
jocis 0:ef402fb370c5 107 * @param inPin Pin number of input pin. All port pins except p19 and p20
jocis 0:ef402fb370c5 108 * @param type Type of edge detection.
jocis 0:ef402fb370c5 109 * @param timeout Timeout in seconds to handle an offline pulse-generator (standing motor). Max 15 minutes.
jocis 0:ef402fb370c5 110 */
jocis 1:6eb686d7d16a 111 explicit Pulses(PinName inPin, PulseType type = RISE, unsigned int timeout=600, unsigned int counter=0);
jocis 0:ef402fb370c5 112
jocis 0:ef402fb370c5 113 /** Gets the frequency based on the last 2 pulses
jocis 0:ef402fb370c5 114 *
jocis 1:6eb686d7d16a 115 * @return Actual frequencey
jocis 0:ef402fb370c5 116 */
jocis 0:ef402fb370c5 117 float getAct();
jocis 0:ef402fb370c5 118
jocis 1:6eb686d7d16a 119 /** Gets the average of frequency based on all pulses since last call of this function
jocis 0:ef402fb370c5 120 *
jocis 0:ef402fb370c5 121 * @return Average frequency. -1 if no new pulses occoured since last call
jocis 0:ef402fb370c5 122 */
jocis 0:ef402fb370c5 123 float getAverage();
jocis 0:ef402fb370c5 124
jocis 1:6eb686d7d16a 125 /** Gets the average, min, max and summ of frequency based on all pulses since last call of this function
jocis 1:6eb686d7d16a 126 *
jocis 1:6eb686d7d16a 127 * @param pAverage Pointer to float value to return average frequency. Use NULL to skip param. -1 if no new pulses occoured since last call.
jocis 1:6eb686d7d16a 128 * @param pMin Pointer to float value to return min. frequency. Use NULL to skip param. -1 if no new pulses occoured since last call.
jocis 1:6eb686d7d16a 129 * @param pMax Pointer to float value to return max. frequency. Use NULL to skip param. -1 if no new pulses occoured since last call.
jocis 1:6eb686d7d16a 130 * @param pSum Pointer to float value to return the accumulated average values. Use NULL to skip param.
jocis 1:6eb686d7d16a 131 */
jocis 1:6eb686d7d16a 132 void get(float *pAverage, float *pMin, float *pMax, float *pSum=NULL);
jocis 1:6eb686d7d16a 133
jocis 0:ef402fb370c5 134 /** Gets the number of pulses since start
jocis 0:ef402fb370c5 135 *
jocis 0:ef402fb370c5 136 * @return Number of pulses
jocis 0:ef402fb370c5 137 */
jocis 0:ef402fb370c5 138 unsigned int getCounter();
jocis 0:ef402fb370c5 139
jocis 0:ef402fb370c5 140 /** Sets the factor for the getter-functions to convert in another unit (1.0=Hz, 60.0=rpm, ...)
jocis 0:ef402fb370c5 141 *
jocis 0:ef402fb370c5 142 * @param factor Factor to scale from Hz to user unit
jocis 0:ef402fb370c5 143 */
jocis 0:ef402fb370c5 144 void setFactor(float factor);
jocis 0:ef402fb370c5 145
jocis 0:ef402fb370c5 146
jocis 0:ef402fb370c5 147 protected:
jocis 0:ef402fb370c5 148
jocis 0:ef402fb370c5 149 void callback_in();
jocis 0:ef402fb370c5 150 void callback_timeout();
jocis 0:ef402fb370c5 151
jocis 0:ef402fb370c5 152 InterruptIn _in;
jocis 0:ef402fb370c5 153 TimerDiff _timer;
jocis 0:ef402fb370c5 154 Ticker _timeout;
jocis 0:ef402fb370c5 155
jocis 0:ef402fb370c5 156 PulseType _type;
jocis 0:ef402fb370c5 157
jocis 0:ef402fb370c5 158 unsigned int _ActTime;
jocis 1:6eb686d7d16a 159 unsigned int _MinTime;
jocis 1:6eb686d7d16a 160 unsigned int _MaxTime;
jocis 1:6eb686d7d16a 161 unsigned int _AvrTimeSum;
jocis 1:6eb686d7d16a 162 unsigned int _AvrTimeCount;
jocis 0:ef402fb370c5 163 unsigned int _Counter;
jocis 0:ef402fb370c5 164 float _Factor;
jocis 0:ef402fb370c5 165 bool _bFirst;
jocis 0:ef402fb370c5 166 unsigned int _Timeout;
jocis 0:ef402fb370c5 167 unsigned int _TimeoutCount;
jocis 0:ef402fb370c5 168
jocis 0:ef402fb370c5 169 };
jocis 0:ef402fb370c5 170
jocis 0:ef402fb370c5 171 #endif