Diff: main.cpp

Revision:

1:55c36e464885

Parent:

0:bd554f9d9a54

Child:

2:9bab1d673af9

--- a/main.cpp	Tue Nov 15 10:04:05 2016 +0000
+++ b/main.cpp	Fri Nov 18 15:53:34 2016 +0000
@@ -1,11 +1,14 @@
 #include "mbed.h"
 
+#define VREF                   3300.0f    /* Device power supply in mV */
+
+// Parameters for temperature sensor only
 #define AMBIENT_TEMP             25.0f    /* Ambient Temperature in °C */
 #define VSENS_AT_AMBIENT_TEMP   760.0f    /* VSENSE value in mV at ambient temperature */
 #define AVG_SLOPE                25.0f    /* Average slope in mV/°C multiplied by 10 */
-#define VREF                   3300.0f    /* Device power supply in mV */
 
-AnalogIn tempsensor(ADC_TEMP);
+//AnalogIn vbat(ADC_VBAT); // To measure VBat
+AnalogIn tempsensor(ADC_TEMP); // To measure Temperature sensot
 
 DigitalOut led(LED1);
 
@@ -14,10 +17,20 @@
     float meas_f;
     float JTemp_f;
 
-    printf("\nSTM32 Internal Temperature Sensor example\n");
+    printf("\nSTM32 Internal Channels example\n");
 
     while(1) {
 
+        /*
+        Note 1: As VBAT voltage could be higher than VDDA, to ensure the correct operation of the ADC, the
+        VBAT pin is internally connected to a bridge divider by 4.
+        Note 2: On some devices the VBAT and temperature sensor are connected to the same ADC internal channel
+        Only one conversion, either temperature sensor or VBAT, must be selected at a time.
+        When both conversion are enabled simultaneously, only the VBAT conversion is
+        performed.
+        */
+        //printf("\nVBat = %.1f mV\n", vbat.read() * VREF * 4);
+
         meas_f = tempsensor.read();
 
         /* Compute the Junction Temperature value