Enable ADC scaling and enable internal channels

Increases input range by 2x(now, 0-2.4v)

Author: Keyur Hariya

targets/TARGET_Maxim/TARGET_MAX32625/PeripheralPins.c

@@ -163,6 +163,10 @@ const PinMap PinMap_ADC[] = {
     { AIN_3, ADC, ADC_CH_3 },
     { AIN_4, ADC, ADC_CH_0_DIV_5 },
     { AIN_5, ADC, ADC_CH_1_DIV_5 },
+    { AIN_6, ADC, ADC_CH_VDDB_DIV_4 },
+    { AIN_7, ADC, ADC_CH_VDD18 },
+    { AIN_8, ADC, ADC_CH_VDD12 },
+    { AIN_9, ADC, ADC_CH_VRTC_DIV_2 },
     { NC,    NC,  0 }
 };
 

targets/TARGET_Maxim/TARGET_MAX32625/TARGET_MAX32625MBED/PinNames.h

@@ -60,7 +60,7 @@ typedef enum {
     P4_0 = (4 << PORT_SHIFT), P4_1, P4_2, P4_3, P4_4, P4_5, P4_6, P4_7,
 
     // Analog input pins
-    AIN_0 = (0xA << PORT_SHIFT), AIN_1, AIN_2, AIN_3, AIN_4, AIN_5,
+    AIN_0 = (0xA << PORT_SHIFT), AIN_1, AIN_2, AIN_3, AIN_4, AIN_5, AIN_6, AIN_7, AIN_8, AIN_9,
 
     LED_GREEN  = P3_1,
     LED_RED    = P3_0,

targets/TARGET_Maxim/TARGET_MAX32625/TARGET_MAX32625NEXPAQ/PinNames.h

@@ -60,7 +60,7 @@ typedef enum {
     P4_0 = (4 << PORT_SHIFT), P4_1, P4_2, P4_3, P4_4, P4_5, P4_6, P4_7,
 
     // Analog input pins
-    AIN_0 = (0xA << PORT_SHIFT), AIN_1, AIN_2, AIN_3, AIN_4, AIN_5,
+    AIN_0 = (0xA << PORT_SHIFT), AIN_1, AIN_2, AIN_3, AIN_4, AIN_5, AIN_6, AIN_7, AIN_8, AIN_9,
 
     // LEDs
     LED1 = P2_4,

targets/TARGET_Maxim/TARGET_MAX32625/analogin_api.c

@@ -65,7 +65,7 @@ float analogin_read(analogin_t *obj)
     float result;
 
     // Start conversion with no input scaling and no input buffer bypass
-    ADC_StartConvert(obj->channel, 0, 0);
+    ADC_StartConvert(obj->channel, 1, 0);
 
     if (ADC_GetData(&tmp) == E_OVERFLOW) {
         result = FLOAT_FULL_SCALE;
@@ -83,7 +83,7 @@ uint16_t analogin_read_u16(analogin_t *obj)
     uint16_t result;
 
     // Start conversion with no input scaling and no input buffer bypass
-    ADC_StartConvert(obj->channel, 0, 0);
+    ADC_StartConvert(obj->channel, 1, 0);
 
     if (ADC_GetData(&tmp) == E_OVERFLOW) {
         result = INT_FULL_SCALE;