Fixed temperature ADC conversion bug on mbxxx.

The conversion was made from an incorrect source when
the GPIO pin was not PB7.
Added functions and macros used to select the correct
ADC channel.

cpu/stm32w108/hal/micro/adc.h

@@ -92,15 +92,15 @@ enum
 #if defined (CORTEXM3)
   /** Channel 0 : ADC0 on PB5 */
 #define ADC_MUX_ADC0    0x0
-  /** Channel 1 : ADC0 on PB6 */
+  /** Channel 1 : ADC1 on PB6 */
 #define ADC_MUX_ADC1    0x1
-  /** Channel 2 : ADC0 on PB7 */
+  /** Channel 2 : ADC2 on PB7 */
 #define ADC_MUX_ADC2    0x2
-  /** Channel 3 : ADC0 on PC1 */
+  /** Channel 3 : ADC3 on PC1 */
 #define ADC_MUX_ADC3    0x3
-  /** Channel 4 : ADC0 on PA4 */
+  /** Channel 4 : ADC4 on PA4 */
 #define ADC_MUX_ADC4    0x4
-  /** Channel 5 : ADC0 on PA5 */
+  /** Channel 5 : ADC5 on PA5 */
 #define ADC_MUX_ADC5    0x5
   /** Channel 8 : VSS (0V) - not for high voltage range */
 #define ADC_MUX_GND     0x8
@@ -127,9 +127,11 @@ enum
   ADC_SOURCE_ADC3_VREF2  = ((ADC_MUX_ADC3  <<ADC_MUXN_BITS) + ADC_MUX_VREF2),
   ADC_SOURCE_ADC3_GND    = ((ADC_MUX_ADC3  <<ADC_MUXN_BITS) + ADC_MUX_GND),
 
-  ADC_SOURCE_ADC4_VREF2  = ((ADC_MUX_ADC4  <<ADC_MUXN_BITS) + ADC_MUX_GND),
+  ADC_SOURCE_ADC4_VREF2  = ((ADC_MUX_ADC4  <<ADC_MUXN_BITS) + ADC_MUX_VREF2),
+  ADC_SOURCE_ADC4_GND    = ((ADC_MUX_ADC4  <<ADC_MUXN_BITS) + ADC_MUX_GND),
 
-  ADC_SOURCE_ADC5_VREF2  = ((ADC_MUX_ADC5  <<ADC_MUXN_BITS) + ADC_MUX_GND),
+  ADC_SOURCE_ADC5_VREF2  = ((ADC_MUX_ADC5  <<ADC_MUXN_BITS) + ADC_MUX_VREF2),
+  ADC_SOURCE_ADC5_GND    = ((ADC_MUX_ADC5  <<ADC_MUXN_BITS) + ADC_MUX_GND),  
 
   ADC_SOURCE_ADC1_ADC0   = ((ADC_MUX_ADC1  <<ADC_MUXN_BITS) + ADC_MUX_ADC0),
   ADC_SOURCE_ADC0_ADC1   = ((ADC_MUX_ADC1  <<ADC_MUXN_BITS) + ADC_MUX_ADC0),
@@ -159,6 +161,12 @@ enum
   ADC_SOURCE_VREG2_VREF2 = ((ADC_MUX_VREG2 <<ADC_MUXN_BITS) + ADC_MUX_VREF2),
   ADC_SOURCE_VDD_GND     = ((ADC_MUX_VREG2 <<ADC_MUXN_BITS) + ADC_MUX_GND)
 };
+
+/** @brief Macro that returns the ADCChannelType, from a given couple of sources
+ * (positive and negative). To be used with halStartAdcConversion().
+ */
+#define ADC_SOURCE(P,N)   (( P << ADC_MUXN_BITS ) + N)
+
 #endif // defined (CORTEXM3)
 
 
@@ -167,6 +175,17 @@ enum
  */
 typedef int8u ADCChannelType;
 
+/** @brief Returns the ADC channel from a given GPIO. Its value can can be used
+ * inside the ADC_SOURCE(P,N) macro to retrieve the input pair for
+ * halStartAdcConversion().
+ *
+ * @param io  The GPIO pin (it can be specified with the convenience macros
+ *            PORTA_PIN(), PORTB_PIN(), PORTC_PIN() )
+ * 
+ * @return The ADC_MUX value connected to the given GPIO.
+ */
+int8u halGetADCChannelFromGPIO(int32u io);
+
 
 /** @brief Initializes and powers-up the ADC. 
  */
@@ -294,6 +313,7 @@ boolean halAdcGetRange(void);
 #ifdef CORTEXM3_STM32F103
 #include "micro/cortexm3/stm32f103ret/adc.h"
 #endif /* CORTEXM3_STM32F103 */
+
 #endif // __ADC_H__
 
 /** @} // END addtogroup

cpu/stm32w108/hal/micro/cortexm3/adc.c

@@ -348,3 +348,34 @@ int16s halConvertValueToVolts(int16u value)
   }
   return V;
 }
+
+int8u halGetADCChannelFromGPIO(int32u io)
+{
+	switch(io)
+	{
+	case PORTB_PIN(5):
+		return ADC_MUX_ADC0;
+			
+	case PORTB_PIN(6):
+		return ADC_MUX_ADC1;
+		
+	case PORTB_PIN(7):
+		return ADC_MUX_ADC2;
+		
+	case PORTC_PIN(1):
+		return ADC_MUX_ADC3;
+		
+	case PORTA_PIN(4):
+		return ADC_MUX_ADC4;
+		
+	case PORTA_PIN(5):
+		return ADC_MUX_ADC5;
+		
+	case PORTB_PIN(0):
+		return ADC_MUX_VREF;
+		
+	default :
+		return 0x0F; // Invalid analogue source
+			
+	}
+}

cpu/stm32w108/hal/micro/cortexm3/temperature_sensor.c

@@ -40,7 +40,7 @@ int32u temperatureSensor_GetValue(void)
      (see STM32W108 errata). As consequence, it is not reccomended to use this ADC driver for getting
      the temperature values. 
     */
-    halStartAdcConversion(ADC_USER_APP, ADC_REF_INT, ADC_SOURCE_ADC2_VREF2, ADC_CONVERSION_TIME_US_4096);
+    halStartAdcConversion(ADC_USER_APP, ADC_REF_INT, ADC_SOURCE(halGetADCChannelFromGPIO(TEMPERATURE_SENSOR_GPIO),ADC_MUX_VREF2), ADC_CONVERSION_TIME_US_4096);
   
     halReadAdcBlocking(ADC_USER_APP, &ADCvalue); // This blocks for a while, about 4ms.
   

platform/mbxxx/dev/temperature-sensor.c

@@ -72,7 +72,7 @@ value(int type)
   static int16u ADCvalue;
   static int16s volts;
   
-  halStartAdcConversion(ADC_USER_APP, ADC_REF_INT, ADC_SOURCE_ADC2_VREF2, ADC_CONVERSION_TIME_US_4096);
+  halStartAdcConversion(ADC_USER_APP, ADC_REF_INT, ADC_SOURCE(halGetADCChannelFromGPIO(TEMPERATURE_SENSOR_GPIO),ADC_MUX_VREF2), ADC_CONVERSION_TIME_US_4096);
   
   halReadAdcBlocking(ADC_USER_APP, &ADCvalue); // This blocks for a while, about 4ms.