CO2 Sensor MH-Z19 Class (uses interrupt input as PWM input)

Dependencies:   mbed

Files at this revision

API Documentation at this revision

Comitter:
zeus3110
Date:
Thu Aug 11 00:41:23 2016 +0000
Commit message:
Initial Release

Changed in this revision

MH_Z19.cpp Show annotated file Show diff for this revision Revisions of this file
MH_Z19.h Show annotated file Show diff for this revision Revisions of this file
main.cpp Show annotated file Show diff for this revision Revisions of this file
mbed.bld Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 3c154d34f47e MH_Z19.cpp
--- /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();
+}
diff -r 000000000000 -r 3c154d34f47e MH_Z19.h
--- /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
diff -r 000000000000 -r 3c154d34f47e main.cpp
--- /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);
+    }
+}
diff -r 000000000000 -r 3c154d34f47e mbed.bld
--- /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