This programm works with Chineese Soil Moisture Sensors YL-69. Read Analog value from A0 pin and out percent of Soil Moisture to UART .

Dependencies:   mbed-STM32F103C8T6 mbed

Revision:
3:6a2c1d1cc937
Parent:
2:38c1190c9ac7
--- a/main.cpp	Fri Jun 08 16:22:39 2018 +0000
+++ b/main.cpp	Sat Jun 09 01:15:49 2018 +0000
@@ -12,19 +12,22 @@
 int main()
 {
     float meas;
-    float very_hum_value = 0.30;
+    float very_hum_value = 0.27;
     float soil_hum_perc;
-    
-     
+         
     AnalogIn analog_value(A0);
-    
+    DigitalOut VCC(PB_7);
     
     while(1) {
+       
+        VCC = 1;// VCC on
         wait(1);
         meas = analog_value.read();
+        VCC = 0; //VCC of
         
         soil_hum_perc = (1 - (meas - very_hum_value)/(1 - very_hum_value)) * 100; // perevod v %
-        pc.printf("Soil_Humidity: %f %\n", soil_hum_perc);
-        //myled = !myled;
+        pc.printf("Soil_Humidity: %f %% \n", soil_hum_perc);
+        
+        wait(600); //period izmereniy
     }
 }