Add support for onRadioNotification(). Radio Notification is a feature that

enables ACTIVE and INACTIVE (nACTIVE) signals from the stack that notify the
  application when the radio is in use. The ACTIVE signal is sent before the
  Radio Event starts. The nACTIVE signal is sent at the end of the Radio
  Event. These signals can be used by the application programmer to
  synchronize application logic with radio activity. For example, the ACTIVE
  signal can be used to shut off external devices to manage peak current drawn
  during periods when the radio is on, or to trigger sensor data collection
  for transmission in the Radio Event.

Bugfixes
~~~~~~~~

none.

nRF51Gap.h

@@ -24,6 +24,9 @@
 #include "GapAdvertisingData.h"
 #include "public/Gap.h"
 
+#include "nrf_soc.h"
+#include "ble_radio_notification.h"
+
 /**************************************************************************/
 /*!
     \brief
@@ -63,6 +66,11 @@ public:
     virtual ble_error_t setPreferredConnectionParams(const ConnectionParams_t *params);
     virtual ble_error_t updateConnectionParams(Handle_t handle, const ConnectionParams_t *params);
 
+    virtual void setOnRadioNotification(RadioNotificationEventCallback_t callback) {
+        Gap::setOnRadioNotification(callback);
+        ble_radio_notification_init(NRF_APP_PRIORITY_HIGH, NRF_RADIO_NOTIFICATION_DISTANCE_NONE, onRadioNotification);
+    }
+
 private:
     uint16_t m_connectionHandle;
     nRF51Gap() {

nordic-sdk/components/ble/ble_radio_notification/ble_radio_notification.c

@@ -0,0 +1,59 @@
+/* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
+ *
+ * The information contained herein is property of Nordic Semiconductor ASA.
+ * Terms and conditions of usage are described in detail in NORDIC
+ * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
+ *
+ * Licensees are granted free, non-transferable use of the information. NO
+ * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
+ * the file.
+ */
+
+#include "ble_radio_notification.h"
+#include <stdlib.h>
+
+
+static bool                                 m_radio_active = false;  /**< Current radio state. */
+static ble_radio_notification_evt_handler_t m_evt_handler  = NULL;   /**< Application event handler for handling Radio Notification events. */
+
+
+void SWI1_IRQHandler(void)
+{
+    m_radio_active = !m_radio_active;
+    if (m_evt_handler != NULL)
+    {
+        m_evt_handler(m_radio_active);
+    }
+}
+
+
+uint32_t ble_radio_notification_init(nrf_app_irq_priority_t               irq_priority,
+                                     nrf_radio_notification_distance_t    distance,
+                                     ble_radio_notification_evt_handler_t evt_handler)
+{
+    uint32_t err_code;
+
+    m_evt_handler = evt_handler;
+
+    // Initialize Radio Notification software interrupt
+    err_code = sd_nvic_ClearPendingIRQ(SWI1_IRQn);
+    if (err_code != NRF_SUCCESS)
+    {
+        return err_code;
+    }
+
+    err_code = sd_nvic_SetPriority(SWI1_IRQn, irq_priority);
+    if (err_code != NRF_SUCCESS)
+    {
+        return err_code;
+    }
+
+    err_code = sd_nvic_EnableIRQ(SWI1_IRQn);
+    if (err_code != NRF_SUCCESS)
+    {
+        return err_code;
+    }
+
+    // Configure the event
+    return sd_radio_notification_cfg_set(NRF_RADIO_NOTIFICATION_TYPE_INT_ON_BOTH, distance);
+}

nordic-sdk/components/ble/ble_radio_notification/ble_radio_notification.h

@@ -0,0 +1,53 @@
+/* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
+ *
+ * The information contained herein is property of Nordic Semiconductor ASA.
+ * Terms and conditions of usage are described in detail in NORDIC
+ * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
+ *
+ * Licensees are granted free, non-transferable use of the information. NO
+ * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
+ * the file.
+ */
+
+/** @file
+ *
+ * @defgroup ble_radio_notification Radio Notification Event Handler
+ * @{
+ * @ingroup ble_sdk_lib
+ * @brief Module for propagating Radio Notification events to the application.
+ */
+
+#ifndef BLE_RADIO_NOTIFICATION_H__
+#define BLE_RADIO_NOTIFICATION_H__
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "nrf_soc.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**@brief Application radio notification event handler type. */
+typedef void (*ble_radio_notification_evt_handler_t) (bool radio_active);
+
+/**@brief Function for initializing the Radio Notification module.
+ *
+ * @param[in]  irq_priority   Interrupt priority for the Radio Notification interrupt handler.
+ * @param[in]  distance       The time from an Active event until the radio is activated.
+ * @param[in]  evt_handler    Handler to be executed when a radio notification event has been
+ *                            received.
+ *
+ * @return     NRF_SUCCESS on successful initialization, otherwise an error code.
+ */
+uint32_t ble_radio_notification_init(nrf_app_irq_priority_t               irq_priority,
+                                     nrf_radio_notification_distance_t    distance,
+                                     ble_radio_notification_evt_handler_t evt_handler);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // BLE_RADIO_NOTIFICATION_H__
+
+/** @} */