Giles Barton-Owen / PWMAverage

A PWM/duty cycle measurement library using Timer2

Dependents:   PWMAverage_test pwm_duty_measurement

PWMAverage.h@0:5da51898a166, 2012-08-29 (annotated)

Committer:
p07gbar
Date:
Wed Aug 29 11:25:55 2012 +0000
Revision:
0:5da51898a166
Child:
1:34a9269390d9
Initial commit

Who changed what in which revision?

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p07gbar 0:5da51898a166 1 /**
p07gbar 0:5da51898a166 2 * @author Giles Barton-Owen
p07gbar 0:5da51898a166 3 *
p07gbar 0:5da51898a166 4 * @section LICENSE
p07gbar 0:5da51898a166 5 *
p07gbar 0:5da51898a166 6 * Copyright (c) 2011 mbed
p07gbar 0:5da51898a166 7 *
p07gbar 0:5da51898a166 8 * Permission is hereby granted, free of charge, to any person obtaining a copy
p07gbar 0:5da51898a166 9 * of this software and associated documentation files (the "Software"), to deal
p07gbar 0:5da51898a166 10 * in the Software without restriction, including without limitation the rights
p07gbar 0:5da51898a166 11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
p07gbar 0:5da51898a166 12 * copies of the Software, and to permit persons to whom the Software is
p07gbar 0:5da51898a166 13 * furnished to do so, subject to the following conditions:
p07gbar 0:5da51898a166 14 *
p07gbar 0:5da51898a166 15 * The above copyright notice and this permission notice shall be included in
p07gbar 0:5da51898a166 16 * all copies or substantial portions of the Software.
p07gbar 0:5da51898a166 17 *
p07gbar 0:5da51898a166 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
p07gbar 0:5da51898a166 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
p07gbar 0:5da51898a166 20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
p07gbar 0:5da51898a166 21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
p07gbar 0:5da51898a166 22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
p07gbar 0:5da51898a166 23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
p07gbar 0:5da51898a166 24 * THE SOFTWARE.
p07gbar 0:5da51898a166 25 *
p07gbar 0:5da51898a166 26 * @section DESCRIPTION
p07gbar 0:5da51898a166 27 * PWM/Duty cycle measurement library using Timer2: library h file for NXP LPC1768
p07gbar 0:5da51898a166 28 *
p07gbar 0:5da51898a166 29 */
p07gbar 0:5da51898a166 30
p07gbar 0:5da51898a166 31 #ifndef PWMAVERAGE_H
p07gbar 0:5da51898a166 32 #define PWMAVERAGE_H
p07gbar 0:5da51898a166 33 #include "mbed.h"
p07gbar 0:5da51898a166 34
p07gbar 0:5da51898a166 35
p07gbar 0:5da51898a166 36 /** A class for measuring PWM/Duty cycle of a signal connected to pins 30 and 29
p07gbar 0:5da51898a166 37 *
p07gbar 0:5da51898a166 38 */
p07gbar 0:5da51898a166 39 class PWMAverage
p07gbar 0:5da51898a166 40 {
p07gbar 0:5da51898a166 41 public:
p07gbar 0:5da51898a166 42 /** Create a PWMAverage object
p07gbar 0:5da51898a166 43 *
p07gbar 0:5da51898a166 44 *
p07gbar 0:5da51898a166 45 * @param cap0 Pin connected to signal (ignored in program)
p07gbar 0:5da51898a166 46 * @param cap1 Pin connected to signal (ignored in program)
p07gbar 0:5da51898a166 47 */
p07gbar 0:5da51898a166 48 PWMAverage(PinName cap0, PinName cap1);
p07gbar 0:5da51898a166 49
p07gbar 0:5da51898a166 50 /** Reset the counters and values
p07gbar 0:5da51898a166 51 */
p07gbar 0:5da51898a166 52 void reset();
p07gbar 0:5da51898a166 53 /** Start the timer
p07gbar 0:5da51898a166 54 */
p07gbar 0:5da51898a166 55 void start();
p07gbar 0:5da51898a166 56 /** Stop the timer
p07gbar 0:5da51898a166 57 */
p07gbar 0:5da51898a166 58 void stop();
p07gbar 0:5da51898a166 59 /** Read the duty cycle measured
p07gbar 0:5da51898a166 60 * @returns The Duty cycle
p07gbar 0:5da51898a166 61 */
p07gbar 0:5da51898a166 62 float read();
p07gbar 0:5da51898a166 63 /** Read the average length of time the signal was high per cycle in seconds
p07gbar 0:5da51898a166 64 * @returns The Length of time the signal was high per cycle in seconds
p07gbar 0:5da51898a166 65 */
p07gbar 0:5da51898a166 66 double avg_up();
p07gbar 0:5da51898a166 67 /** Read the average length of time the signal was high per cycle in seconds
p07gbar 0:5da51898a166 68 * @returns The Length of time the signal was high per cycle in seconds
p07gbar 0:5da51898a166 69 */
p07gbar 0:5da51898a166 70 float avg_UP();
p07gbar 0:5da51898a166 71 /** Read the average length of time the signal was low per cycle in seconds
p07gbar 0:5da51898a166 72 * @returns The Length of time the signal was low per cycle in seconds
p07gbar 0:5da51898a166 73 */
p07gbar 0:5da51898a166 74 double avg_down();
p07gbar 0:5da51898a166 75 /** Read the average period in seconds
p07gbar 0:5da51898a166 76 * @returns The Period
p07gbar 0:5da51898a166 77 */
p07gbar 0:5da51898a166 78 double period();
p07gbar 0:5da51898a166 79 /** Read the number of cycles counted over
p07gbar 0:5da51898a166 80 * @returns The number of cycles
p07gbar 0:5da51898a166 81 */
p07gbar 0:5da51898a166 82 int count();
p07gbar 0:5da51898a166 83
p07gbar 0:5da51898a166 84 long count_;
p07gbar 0:5da51898a166 85 long totalup;
p07gbar 0:5da51898a166 86 long total;
p07gbar 0:5da51898a166 87
p07gbar 0:5da51898a166 88 double timeMult;
p07gbar 0:5da51898a166 89
p07gbar 0:5da51898a166 90 double timeDiv;
p07gbar 0:5da51898a166 91
p07gbar 0:5da51898a166 92 private:
p07gbar 0:5da51898a166 93
p07gbar 0:5da51898a166 94 static void _tisr();
p07gbar 0:5da51898a166 95 static PWMAverage * instance;
p07gbar 0:5da51898a166 96 void enable(bool yn);
p07gbar 0:5da51898a166 97 void configure();
p07gbar 0:5da51898a166 98
p07gbar 0:5da51898a166 99
p07gbar 0:5da51898a166 100
p07gbar 0:5da51898a166 101 bool running;
p07gbar 0:5da51898a166 102 bool starting;
p07gbar 0:5da51898a166 103
p07gbar 0:5da51898a166 104 uint32_t prescaler_point;
p07gbar 0:5da51898a166 105
p07gbar 0:5da51898a166 106 };
p07gbar 0:5da51898a166 107
p07gbar 0:5da51898a166 108
p07gbar 0:5da51898a166 109 #endif