diff --git a/hal/inc/adc_hal.h b/hal/inc/adc_hal.h
index 862407651b..b6feb44beb 100644
--- a/hal/inc/adc_hal.h
+++ b/hal/inc/adc_hal.h
@@ -31,7 +31,13 @@
 #include "pinmap_hal.h"
 
 /* Exported types ------------------------------------------------------------*/
-
+#if (PLATFORM_ID == PLATFORM_ARGON) || (PLATFORM_ID == PLATFORM_BORON) || (PLATFORM_ID == PLATFORM_XENON)
+typedef enum
+{
+    AR_DEFAULT,
+    INTERNAL,
+} vref_e;
+#endif
 /* Exported constants --------------------------------------------------------*/
 
 /* Exported macros -----------------------------------------------------------*/
@@ -46,6 +52,10 @@ void HAL_ADC_Set_Sample_Time(uint8_t ADC_SampleTime);
 int32_t HAL_ADC_Read(pin_t pin);
 void HAL_ADC_DMA_Init();
 
+#if (PLATFORM_ID == PLATFORM_ARGON) || (PLATFORM_ID == PLATFORM_BORON) || (PLATFORM_ID == PLATFORM_XENON)
+void HAL_ADC_Set_VREF(vref_e v_e);
+#endif
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/hal/inc/hal_dynalib_gpio.h b/hal/inc/hal_dynalib_gpio.h
index 0bb3f76af6..ff8245bd4b 100644
--- a/hal/inc/hal_dynalib_gpio.h
+++ b/hal/inc/hal_dynalib_gpio.h
@@ -87,7 +87,8 @@ DYNALIB_FN(34, hal_gpio, HAL_PWM_Get_Max_Frequency, uint32_t(uint16_t))
 DYNALIB_FN(35, hal_gpio, HAL_Interrupts_Detach_Ext, void(uint16_t, uint8_t, void*))
 DYNALIB_FN(36, hal_gpio, HAL_Set_Direct_Interrupt_Handler, int(IRQn_Type irqn, HAL_Direct_Interrupt_Handler handler, uint32_t flags, void* reserved))
 
+DYNALIB_FN(37, hal_gpio, HAL_ADC_Set_VREF, void(vref_e))
+
 DYNALIB_END(hal_gpio)
 
 #endif	/* HAL_DYNALIB_GPIO_H */
-
diff --git a/hal/src/nRF52840/adc_hal.cpp b/hal/src/nRF52840/adc_hal.cpp
index c9d182d61a..9f3181ff4b 100644
--- a/hal/src/nRF52840/adc_hal.cpp
+++ b/hal/src/nRF52840/adc_hal.cpp
@@ -20,15 +20,19 @@
 #include "adc_hal.h"
 #include "pinmap_impl.h"
 
+
 static volatile bool m_adc_initiated = false;
 
-static const nrfx_saadc_config_t saadc_config = 
+static const nrfx_saadc_config_t saadc_config =
 {
     .resolution         = NRF_SAADC_RESOLUTION_12BIT,
     .oversample         = NRF_SAADC_OVERSAMPLE_DISABLED,
     .interrupt_priority = NRFX_SAADC_CONFIG_IRQ_PRIORITY
 };
 
+nrf_saadc_reference_t VREF = NRF_SAADC_REFERENCE_VDD4;
+
+
 static void analog_in_event_handler(nrfx_saadc_evt_t const *p_event)
 {
     (void) p_event;
@@ -39,6 +43,22 @@ void HAL_ADC_Set_Sample_Time(uint8_t ADC_SampleTime)
     // deprecated
 }
 
+/*
+ * @brief @brief Set the ADC reference to either VDD / 4 (AR_DEFAULT) or the internal 0.6v (INTERNAL)
+ */
+#if (PLATFORM_ID == PLATFORM_ARGON) || (PLATFORM_ID == PLATFORM_BORON) || (PLATFORM_ID == PLATFORM_XENON)
+void HAL_ADC_Set_VREF(vref_e v_e){
+    switch (v_e) {
+        case AR_DEFAULT: VREF = NRF_SAADC_REFERENCE_VDD4; break;
+
+        case INTERNAL: VREF = NRF_SAADC_REFERENCE_INTERNAL; break;
+
+        default: VREF = NRF_SAADC_REFERENCE_VDD4; break;
+    }
+
+}
+#endif
+
 /*
  * @brief Read the analog value of a pin.
  * Should return a 16-bit value, 0-65536 (0 = LOW, 65536 = HIGH)
@@ -77,11 +97,11 @@ int32_t HAL_ADC_Read(uint16_t pin)
     }
 
      //Single ended, negative input to ADC shorted to GND.
-    nrf_saadc_channel_config_t channel_config = {                                                   
+    nrf_saadc_channel_config_t channel_config = {
         .resistor_p = NRF_SAADC_RESISTOR_DISABLED,      \
         .resistor_n = NRF_SAADC_RESISTOR_DISABLED,      \
         .gain       = NRF_SAADC_GAIN1_4,                \
-        .reference  = NRF_SAADC_REFERENCE_VDD4,         \
+        .reference  = VREF,                             \
         .acq_time   = NRF_SAADC_ACQTIME_10US,           \
         .mode       = NRF_SAADC_MODE_SINGLE_ENDED,      \
         .burst      = NRF_SAADC_BURST_DISABLED,         \
@@ -117,6 +137,8 @@ int32_t HAL_ADC_Read(uint16_t pin)
     return 0;
 }
 
+
+
 /*
  * @brief Initialize the ADC peripheral.
  */
diff --git a/hal/src/template/adc_hal.cpp b/hal/src/template/adc_hal.cpp
index ea202a7282..23d9685f03 100644
--- a/hal/src/template/adc_hal.cpp
+++ b/hal/src/template/adc_hal.cpp
@@ -39,6 +39,7 @@ int32_t HAL_ADC_Read(uint16_t pin)
     return 0;
 }
 
+
 /*
  * @brief Initialize the ADC peripheral.
  */
diff --git a/user/tests/hal/adc/test_adc.cpp b/user/tests/hal/adc/test_adc.cpp
index 115027d2c0..226bb7183a 100644
--- a/user/tests/hal/adc/test_adc.cpp
+++ b/user/tests/hal/adc/test_adc.cpp
@@ -25,11 +25,15 @@ Serial1LogHandler logHandler(115200);
 /* executes once at startup */
 void setup() {
     HAL_ADC_DMA_Init();
+    #if (PLATFORM_ID == PLATFORM_ARGON) || (PLATFORM_ID == PLATFORM_BORON) || (PLATFORM_ID == PLATFORM_XENON)
+    HAL_ADC_Set_VREF(INTERNAL);
+    HAL_ADC_Set_VREF(AR_DEFAULT);
+    #endif
 }
 
 /* executes continuously after setup() runs */
 void loop() {
-    Log.info("A0: %d, A1: %d, A2: %d, A3: %d, A4: %d, A5: %d", 
+    Log.info("A0: %d, A1: %d, A2: %d, A3: %d, A4: %d, A5: %d",
              HAL_ADC_Read(A0),
              HAL_ADC_Read(A1),
              HAL_ADC_Read(A2),
diff --git a/wiring/inc/spark_wiring.h b/wiring/inc/spark_wiring.h
index efd14d5422..fc7a4a5870 100644
--- a/wiring/inc/spark_wiring.h
+++ b/wiring/inc/spark_wiring.h
@@ -1,7 +1,7 @@
 /**
  ******************************************************************************
  * @file    spark_wiring.h
- * @author  Satish Nair, Zachary Crockett, Zach Supalla and Mohit Bhoite
+ * @author  Satish Nair, Zachary Crockett, Zach Supalla, Mohit Bhoite and Stuart Feichtinger
  * @version V1.0.0
  * @date    13-March-2013
  * @brief   Header for spark_wiring.c module
@@ -51,7 +51,6 @@
 #include "spark_wiring_cloud.h"
 #include "spark_wiring_rgb.h"
 #include "spark_wiring_ticks.h"
-#include "spark_wiring_nfc.h"
 
 /* To prevent build error, we are undefining and redefining DAC here */
 #undef DAC
@@ -67,6 +66,10 @@ extern "C" {
 void setADCSampleTime(uint8_t ADC_SampleTime);
 int32_t analogRead(uint16_t pin);
 
+#if (PLATFORM_ID == PLATFORM_ARGON) || (PLATFORM_ID == PLATFORM_BORON) || (PLATFORM_ID == PLATFORM_XENON)
+void analogReference(vref_e v);
+#endif
+
 /*
 * GPIO
 */
diff --git a/wiring_globals/src/spark_wiring_gpio.cpp b/wiring_globals/src/spark_wiring_gpio.cpp
index 6169703619..3cb2a4547f 100644
--- a/wiring_globals/src/spark_wiring_gpio.cpp
+++ b/wiring_globals/src/spark_wiring_gpio.cpp
@@ -151,7 +151,15 @@ int32_t digitalRead(pin_t pin)
 
     return HAL_GPIO_Read(pin);
 }
+#if (PLATFORM_ID == PLATFORM_ARGON) || (PLATFORM_ID == PLATFORM_BORON) || (PLATFORM_ID == PLATFORM_XENON)
+/*
+ * @brief Set the ADC reference to either VDD / 4 (AR_DEFAULT) or the internal 0.6v (INTERNAL)
+ */
 
+void analogReference(vref_e v){
+    HAL_ADC_Set_VREF(v);
+}
+#endif
 /*
  * @brief Read the analog value of a pin.
  * Should return a 16-bit value, 0-65536 (0 = LOW, 65536 = HIGH)
@@ -178,6 +186,7 @@ int32_t analogRead(pin_t pin)
   return HAL_ADC_Read(pin);
 }
 
+
 /*
  * @brief Should take an integer 0-255 and create a 500Hz PWM signal with a duty cycle from 0-100%.
  * On Photon, DAC1 and DAC2 act as true analog outputs(values: 0 to 4095) using onchip DAC peripheral
@@ -251,7 +260,7 @@ uint8_t analogWriteResolution(pin_t pin, uint8_t value)
     HAL_PWM_Set_Resolution(pin, value);
     return HAL_PWM_Get_Resolution(pin);
   }
-  
+
 
   return 0;
 }