stephen mathenge / Mbed OS Level_estimation_Maesurement

Level measurement using range finder and lora technology

Dependencies:   Cayenne-LPP SDBlockDevice

inc/dust_sensor.h@0:f930f0440fd5, 2019-06-26 (annotated)

Committer:
wamae
Date:
Wed Jun 26 10:35:50 2019 +0000
Revision:
0:f930f0440fd5
better copy

Who changed what in which revision?

UserRevisionLine numberNew contents of line
wamae 0:f930f0440fd5 1 #ifndef _DUST_SENSOR_H
wamae 0:f930f0440fd5 2 #define _DUST_SENSOR_H
wamae 0:f930f0440fd5 3
wamae 0:f930f0440fd5 4 #include "mbed.h"
wamae 0:f930f0440fd5 5
wamae 0:f930f0440fd5 6 class DustSensor : public NonCopyable<DustSensor> {
wamae 0:f930f0440fd5 7 public:
wamae 0:f930f0440fd5 8 DustSensor(PinName pin) : _input(pin), _cb(NULL), _busy(false) {
wamae 0:f930f0440fd5 9
wamae 0:f930f0440fd5 10 }
wamae 0:f930f0440fd5 11
wamae 0:f930f0440fd5 12 bool measure(Callback<void(int, float, float)> cb) {
wamae 0:f930f0440fd5 13 if (_busy) {
wamae 0:f930f0440fd5 14 return false;
wamae 0:f930f0440fd5 15 }
wamae 0:f930f0440fd5 16
wamae 0:f930f0440fd5 17 _cb = cb;
wamae 0:f930f0440fd5 18
wamae 0:f930f0440fd5 19 _busy = true;
wamae 0:f930f0440fd5 20
wamae 0:f930f0440fd5 21 m.attach(callback(this, &DustSensor::calculate), 30.0f);
wamae 0:f930f0440fd5 22 t.reset(); // reset mesurement every 30 seconds
wamae 0:f930f0440fd5 23 _input.fall(callback(this, &DustSensor::start)); // start measuring when signal is low
wamae 0:f930f0440fd5 24 _input.rise(callback(this, &DustSensor::stop)); // stop measuring when signal is high
wamae 0:f930f0440fd5 25
wamae 0:f930f0440fd5 26 return true;
wamae 0:f930f0440fd5 27 }
wamae 0:f930f0440fd5 28
wamae 0:f930f0440fd5 29 bool is_busy() {
wamae 0:f930f0440fd5 30 return _busy;
wamae 0:f930f0440fd5 31 }
wamae 0:f930f0440fd5 32
wamae 0:f930f0440fd5 33 private:
wamae 0:f930f0440fd5 34 // Start Timer
wamae 0:f930f0440fd5 35 void start(void) {
wamae 0:f930f0440fd5 36 t.start();
wamae 0:f930f0440fd5 37 }
wamae 0:f930f0440fd5 38
wamae 0:f930f0440fd5 39 // Stop Timer
wamae 0:f930f0440fd5 40 void stop(void) {
wamae 0:f930f0440fd5 41 t.stop();
wamae 0:f930f0440fd5 42 }
wamae 0:f930f0440fd5 43
wamae 0:f930f0440fd5 44 // calculate sensor value
wamae 0:f930f0440fd5 45 void calculate() {
wamae 0:f930f0440fd5 46 // run measurements
wamae 0:f930f0440fd5 47 int lpo = t.read_us();
wamae 0:f930f0440fd5 48 float ratio = t.read_us() / (30000 * 10.0);
wamae 0:f930f0440fd5 49 float concentration = 1.1 * pow(ratio,3) -3.8 * pow(ratio, 2) + 520 * ratio + 0.62;
wamae 0:f930f0440fd5 50 _cb(lpo, ratio, concentration);
wamae 0:f930f0440fd5 51
wamae 0:f930f0440fd5 52 _busy = false;
wamae 0:f930f0440fd5 53 }
wamae 0:f930f0440fd5 54
wamae 0:f930f0440fd5 55 InterruptIn _input;
wamae 0:f930f0440fd5 56 Callback<void(int, float, float)> _cb;
wamae 0:f930f0440fd5 57
wamae 0:f930f0440fd5 58 bool _busy;
wamae 0:f930f0440fd5 59
wamae 0:f930f0440fd5 60 Timer t; // measure amount of time signal is low
wamae 0:f930f0440fd5 61 Timeout m; // every 30 seconds calculate measurement
wamae 0:f930f0440fd5 62 };
wamae 0:f930f0440fd5 63
wamae 0:f930f0440fd5 64 #endif // _DUST_SENSOR_H