Diff: main.cpp

Revision:

0:fc777b6c55d6

Child:

1:be2eea2ae8e7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Thu Feb 08 08:04:35 2018 +0000
@@ -0,0 +1,74 @@
+/*----------------------------------------------------------------------------
+LAB EXERCISE - Environmental sensors measurments 
+ ----------------------------------------
+    In this exercise we will read the environmental sensors on the Nucleo sensors shield (X-NUCLEO-IKS01A1) 
+    with the help of the ST Nucleo Sensor Shield library which is compatible with the MBED API.
+    Then we will send the measurements via USB to our PC using serial communication. 
+    We can then display the results using a terminal emulation program (e.g. Termite).
+    
+    At the same time the program blinks the on board LED to show alivness. 
+    
+
+    GOOD LUCK!
+ *----------------------------------------------------------------------------*/
+
+#include "mbed.h"
+#include "x_cube_mems.h"
+#include "x_nucleo_iks01a1.h"
+
+// Create a DigitalOut objects for the LED
+DigitalOut led(LED1);
+
+// Create a Serial objects to communicate via USB
+Serial pc(USBTX, USBRX);
+
+// Create 2 Ticker objects for a recurring interrupts. One for blink a LED and the other one to update the sensor lectures periodicly.
+Ticker blinky; 
+Ticker update;
+
+volatile float TEMPERATURE_C;
+volatile float TEMPERATURE_F;
+volatile float TEMPERATURE_K;
+volatile float HUMIDITY;
+volatile float PRESSURE;
+
+bool measurements_update = false;
+
+void blinky_handler(){
+    led = !led;
+}
+
+void sensors_handler(){
+    measurements_update = true;
+}
+
+int main() {
+    
+    /* Create a sensor shield object */
+    static X_CUBE_MEMS *Sensors = X_CUBE_MEMS::Instance();
+    
+    /* Attach a function to be called by the Ticker objects at a specific interval in seconds*/
+    blinky.attach(&blinky_handler, 0.5);
+    update.attach(&sensors_handler, 3);
+    
+    while(1) {
+
+        if(measurements_update == true){
+        /* Read the environmental sensors  */
+        Sensors->hts221.GetTemperature((float *)&TEMPERATURE_C);
+        Sensors->hts221.GetHumidity((float *)&HUMIDITY);
+        Sensors->lps25h.GetPressure((float *)&PRESSURE);
+        
+        TEMPERATURE_F = (TEMPERATURE_C * 1.8f) + 32.0f;     //Convert the temperature from Celsius to Fahrenheit
+        TEMPERATURE_K = (TEMPERATURE_C + 273.15f);          //Convert the temperature from Celsius to Kelvin
+        pc.printf("Temperature:\t %.2f C / %.2f F / %.2f K\r\n", TEMPERATURE_C, TEMPERATURE_F, TEMPERATURE_K);
+        pc.printf("Humidity:\t %.2f%%\r\n", HUMIDITY);
+        pc.printf("Pressure:\t %.2f hPa\r\n", PRESSURE); 
+
+        pc.printf("\r\n");
+                
+        measurements_update = false;
+        }
+        __wfi();
+    }
+}
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