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CO2 Sensor MH-Z19 Class (uses interrupt input as PWM input)
Revision 0:3c154d34f47e, committed 2016-08-11
- Comitter:
- zeus3110
- Date:
- Thu Aug 11 00:41:23 2016 +0000
- Commit message:
- Initial Release
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MH_Z19.cpp Thu Aug 11 00:41:23 2016 +0000 @@ -0,0 +1,45 @@ +/* mbed MH-Z19 Library + * Copyright (c) 2016, zeus3110 + * + * 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 "MH_Z19.h" + +MH_Z19::MH_Z19(PinName p) : Port(p) { + Port.rise(this, &MH_Z19::rise); + Port.fall(this, &MH_Z19::fall); + OnWidth=2; + T.start(); +} + +int MH_Z19::ReadCO2PPM() { + + return ((CO2_MAX_PPM)*(OnWidth-2)/(PWM_CYCLE_MS-4)); + +} + + +void MH_Z19::rise() { + T.reset(); +} + +void MH_Z19::fall() { + OnWidth=T.read_ms(); +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/MH_Z19.h Thu Aug 11 00:41:23 2016 +0000 @@ -0,0 +1,50 @@ +/* mbed MH-Z19 Library + * Copyright (c) 2016, zeus3110 + * + * 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. + */ + +#ifndef MH_Z19_H +#define MH_Z19_H + +#include "mbed.h" + +#define PWM_CYCLE_MS 1004 +#define CO2_MAX_PPM 5000 + +class MH_Z19 { +public: + /** Create a MH_Z19 + * + * @param Port The pwm input pin (must support InterruptIn) + */ + MH_Z19(PinName Port); + + int ReadCO2PPM(); + +protected: + void rise(); + void fall(); + + InterruptIn Port; + Timer T; + int OnWidth; +}; + +#endif
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main.cpp Thu Aug 11 00:41:23 2016 +0000 @@ -0,0 +1,18 @@ +#include "mbed.h" +#include "MH_Z19.h" + +DigitalOut myled(LED1); +MH_Z19 Sen(p5); + +int main() { + + wait(2); + + while(1) { + myled = 1; + wait(0.2); + myled = 0; + printf("CO2 PPM:%d\n",Sen.ReadCO2PPM()); + wait(1.8); + } +}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Thu Aug 11 00:41:23 2016 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/f9eeca106725 \ No newline at end of file