| /* |
| * Author: Jon Trulson <jtrulson@ics.com> |
| * Copyright (c) 2016 Intel Corporation. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining |
| * a copy of this software and associated documentation files (the |
| * "Software"), to deal in the Software without restriction, including |
| * without limitation the rights to use, copy, modify, merge, publish, |
| * distribute, sublicense, and/or sell copies of the Software, and to |
| * permit persons to whom the Software is furnished to do so, subject to |
| * the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be |
| * included in all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
| * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
| * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
| * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
| * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| |
| #include <iostream> |
| |
| #include "cwlsxxa.hpp" |
| |
| using namespace upm; |
| using namespace std; |
| |
| // for current loop reads that seems a little noisy, we average over |
| // several aio reads. |
| static const int maxSamples = 50; |
| |
| // conversion from celcius to fahrenheit |
| |
| static float c2f(float c) |
| { |
| return (c * (9.0 / 5.0) + 32.0); |
| } |
| |
| |
| CWLSXXA::CWLSXXA(int gPin, int hPin, int tPin, float rResistor, float aref) : |
| m_aioCO2(gPin), m_aioHum(0), m_aioTemp(0) |
| { |
| m_hasHum = (hPin >= 0) ? true : false; |
| m_hasTemp = (tPin >= 0) ? true : false; |
| |
| if (m_hasTemp) |
| { |
| m_aioTemp = new mraa::Aio(tPin); |
| m_aResTemp = (1 << m_aioTemp->getBit()); |
| } |
| else |
| m_aResTemp = 0; |
| |
| if (m_hasHum) |
| { |
| m_aioHum = new mraa::Aio(hPin); |
| m_aResHum = (1 << m_aioHum->getBit()); |
| } |
| else |
| m_aResHum = 0; |
| |
| m_aResCO2 = (1 << m_aioCO2.getBit()); |
| |
| m_temperature = 0.0; |
| m_humidity = 0.0; |
| m_co2 = 0.0; |
| |
| m_aref = aref; |
| m_rResistor = rResistor; |
| } |
| |
| CWLSXXA::~CWLSXXA() |
| { |
| if (m_aioHum) |
| delete m_aioHum; |
| if (m_aioTemp) |
| delete m_aioTemp; |
| } |
| |
| void CWLSXXA::update() |
| { |
| // temperature |
| int val; |
| float volts; |
| float milliamps = 0.0; |
| |
| int samples; |
| if (m_rResistor) |
| samples = maxSamples; |
| else |
| samples = 1; |
| |
| |
| // temperature |
| if (m_hasTemp) |
| { |
| // fortunately, this sensor always reports temperatures in C, |
| // regardless of the configuration of the LCD display (for |
| // models that have an LCD display) |
| |
| val = average(m_aioTemp, samples); |
| |
| volts = (float(val) * (m_aref / m_aResTemp)); |
| |
| // valid range is 10-35C, current loop range is 16ma (20ma - 4ma) |
| if (!m_rResistor) |
| m_temperature = ((volts / m_aref) * 25.0) + 10.0; |
| else |
| { |
| milliamps = ((volts / m_rResistor * 1000.0) - 4.0); |
| if (milliamps < 0.0) // not connected |
| milliamps = 0.0; |
| m_temperature = (milliamps * (25.0 / 16.0)) + 10.0; |
| } |
| } |
| |
| // humidity |
| if (m_hasHum) |
| { |
| val = average(m_aioHum, samples); |
| volts = (float(val) * (m_aref / m_aResHum)); |
| |
| // range is 0-100 |
| if (!m_rResistor) |
| m_humidity = ((volts / m_aref) * 100.0); |
| else |
| { |
| milliamps = ((volts / m_rResistor * 1000.0) - 4.0); |
| if (milliamps < 0.0) // not connected |
| milliamps = 0.0; |
| m_humidity = milliamps * (100.0 / 16.0); |
| } |
| } |
| |
| // CO2 |
| val = average(&m_aioCO2, samples); |
| volts = (float(val) * (m_aref / m_aResCO2)); |
| |
| // CO2 range is 0-2000ppm |
| if (!m_rResistor) |
| m_co2 = ((volts / m_aref) * 2000.0); |
| else |
| { |
| milliamps = ((volts / m_rResistor * 1000.0) - 4.0); |
| if (milliamps < 0.0) // not connected |
| milliamps = 0.0; |
| m_co2 = milliamps * (2000.0 / 16.0); |
| } |
| } |
| |
| float CWLSXXA::getTemperature(bool fahrenheit) |
| { |
| if (fahrenheit) |
| return c2f(m_temperature); |
| else |
| return m_temperature; |
| } |
| |
| float CWLSXXA::getHumidity() |
| { |
| return m_humidity; |
| } |
| |
| float CWLSXXA::getCO2() |
| { |
| return m_co2; |
| } |
| |
| int CWLSXXA::average(mraa::Aio *aio, int samples) |
| { |
| if (samples <= 0) |
| samples = 1; |
| |
| int avg = 0; |
| for (int i=0; i<samples; i++) |
| avg += aio->read(); |
| |
| return (avg / samples); |
| } |