Alexandre Bouillot / PwmReader

Pulse measurement to know signal occupancy

Dependents:   PwmReaderTest

PwmReader.cpp@0:15aa9d3aeb2e, 2017-01-25 (annotated)

Committer:
abouillot
Date:
Wed Jan 25 08:52:00 2017 +0000
Revision:
0:15aa9d3aeb2e
Child:
1:ebc39fb22351
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
abouillot 0:15aa9d3aeb2e 1 /*!
abouillot 0:15aa9d3aeb2e 2 * PwmReader.cpp
abouillot 0:15aa9d3aeb2e 3 *
abouillot 0:15aa9d3aeb2e 4 * Read signal occupacy on a pin in a non blocking way using timer and interrupt
abouillot 0:15aa9d3aeb2e 5 *
abouillot 0:15aa9d3aeb2e 6 * Copyright (c) 2017 - Alexandre Bouillot github.com/abouillot
abouillot 0:15aa9d3aeb2e 7 *
abouillot 0:15aa9d3aeb2e 8 * Permission is hereby granted, free of charge, to any person obtaining a copy
abouillot 0:15aa9d3aeb2e 9 * of this software and associated documnetation files (the "Software"), to deal
abouillot 0:15aa9d3aeb2e 10 * in the Software without restriction, including without limitation the rights
abouillot 0:15aa9d3aeb2e 11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
abouillot 0:15aa9d3aeb2e 12 * copies of the Software, and to permit persons to whom the Software is
abouillot 0:15aa9d3aeb2e 13 * furished to do so, subject to the following conditions:
abouillot 0:15aa9d3aeb2e 14 *
abouillot 0:15aa9d3aeb2e 15 * The above copyright notice and this permission notice shall be included in
abouillot 0:15aa9d3aeb2e 16 * all copies or substantial portions of the Software.
abouillot 0:15aa9d3aeb2e 17 *
abouillot 0:15aa9d3aeb2e 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
abouillot 0:15aa9d3aeb2e 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
abouillot 0:15aa9d3aeb2e 20 * FITNESS OR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
abouillot 0:15aa9d3aeb2e 21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
abouillot 0:15aa9d3aeb2e 22 * LIABILITY WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
abouillot 0:15aa9d3aeb2e 23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
abouillot 0:15aa9d3aeb2e 24 * THE SOFTWARE.
abouillot 0:15aa9d3aeb2e 25 */
abouillot 0:15aa9d3aeb2e 26
abouillot 0:15aa9d3aeb2e 27 #include "PwmReader.h"
abouillot 0:15aa9d3aeb2e 28
abouillot 0:15aa9d3aeb2e 29
abouillot 0:15aa9d3aeb2e 30 void PwmReader::pressedInt()
abouillot 0:15aa9d3aeb2e 31 {
abouillot 0:15aa9d3aeb2e 32 _high += _timer.read_us() - _last_toggle;
abouillot 0:15aa9d3aeb2e 33 _last_toggle = _timer.read_us();
abouillot 0:15aa9d3aeb2e 34 // _timer.reset();
abouillot 0:15aa9d3aeb2e 35 // printf("p %ld ", _high);
abouillot 0:15aa9d3aeb2e 36 // sleep();
abouillot 0:15aa9d3aeb2e 37 }
abouillot 0:15aa9d3aeb2e 38
abouillot 0:15aa9d3aeb2e 39 void PwmReader::releasedInt()
abouillot 0:15aa9d3aeb2e 40 {
abouillot 0:15aa9d3aeb2e 41 _down += _timer.read_us() - _last_toggle;
abouillot 0:15aa9d3aeb2e 42 _last_toggle = _timer.read_us();
abouillot 0:15aa9d3aeb2e 43 // _timer.reset();
abouillot 0:15aa9d3aeb2e 44 // printf("r %ld", _down);
abouillot 0:15aa9d3aeb2e 45 // sleep();
abouillot 0:15aa9d3aeb2e 46 }
abouillot 0:15aa9d3aeb2e 47
abouillot 0:15aa9d3aeb2e 48 void PwmReader::init()
abouillot 0:15aa9d3aeb2e 49 {
abouillot 0:15aa9d3aeb2e 50 _pin.fall(callback(this, &PwmReader::pressedInt));
abouillot 0:15aa9d3aeb2e 51 _pin.rise(callback(this, &PwmReader::releasedInt));
abouillot 0:15aa9d3aeb2e 52 }
abouillot 0:15aa9d3aeb2e 53
abouillot 0:15aa9d3aeb2e 54 void PwmReader::start()
abouillot 0:15aa9d3aeb2e 55 {
abouillot 0:15aa9d3aeb2e 56 _high = 0;
abouillot 0:15aa9d3aeb2e 57 _down = 0;
abouillot 0:15aa9d3aeb2e 58 _start_state = _pin.read();
abouillot 0:15aa9d3aeb2e 59 _pin.enable_irq();
abouillot 0:15aa9d3aeb2e 60 _timer.start();
abouillot 0:15aa9d3aeb2e 61 }
abouillot 0:15aa9d3aeb2e 62
abouillot 0:15aa9d3aeb2e 63 void PwmReader::stop()
abouillot 0:15aa9d3aeb2e 64 {
abouillot 0:15aa9d3aeb2e 65 _pin.disable_irq();
abouillot 0:15aa9d3aeb2e 66
abouillot 0:15aa9d3aeb2e 67 if (_high == 0 && _down == 0)
abouillot 0:15aa9d3aeb2e 68 if (_start_state == 0)
abouillot 0:15aa9d3aeb2e 69 _high = _timer.read_us();
abouillot 0:15aa9d3aeb2e 70 else if (_start_state == 1)
abouillot 0:15aa9d3aeb2e 71 _down = _timer.read_us();
abouillot 0:15aa9d3aeb2e 72 _timer.stop();
abouillot 0:15aa9d3aeb2e 73 }