Nordic协议栈与app的调用方式

Nordic是协议栈以hex文件的方式提供，那么app怎么是怎么通过api来调用协议栈的呢。

1. 应用层通过API的方式调用协议栈的函数，通过SVC中断方式。

    当协议栈被使能时，共用了0X10~0XFF，具体来说就是每个API函数对应一个number。

#define SOC_SVC_BASE               (0x20) 

#define BLE_SVC_BASE           0x60       /**< Common BLE SVC base. */

#define BLE_SVC_LAST           0x6B       /**< Common BLE SVC last. */

#define BLE_GAP_SVC_BASE       0x6C       /**< GAP BLE SVC base. */

#define BLE_GAP_SVC_LAST       0x93       /**< GAP BLE SVC last. */

#define BLE_GATTC_SVC_BASE     0x94       /**< GATTC BLE SVC base. */

#define BLE_GATTC_SVC_LAST     0x9F       /**< GATTC BLE SVC last. */

#define BLE_GATTS_SVC_BASE     0xA0       /**< GATTS BLE SVC base. */

#define BLE_GATTS_SVC_LAST     0xAF       /**< GATTS BLE SVC last. */

#define BLE_L2CAP_SVC_BASE     0xB0       /**< L2CAP BLE SVC base. */

#define BLE_L2CAP_SVC_LAST     0xBF       /**< L2CAP BLE SVC last. */

2.而协议栈则通过SWI中断开通知APP.

由上图可以可以看到 SWI用到了SWI1, SWI2, SWI5, 但SWI5是协议栈本身调度使用了。在sdk代码中也体现了这一点。

#define SD_EVT_IRQn                       (SWI2_EGU2_IRQn)        /**< SoftDevice

#define SD_EVT_IRQHandler                 (SWI2_EGU2_IRQHandler)  /**< SoftDevice

#define RADIO_NOTIFICATION_IRQn           (SWI1_EGU1_IRQn)        /**< The radio

#define RADIO_NOTIFICATION_IRQHandler     (SWI1_EGU1_IRQHandler)  /**< The radio