add nrf51822 to bsp

bsp/nrf51822/Libraries/CMSIS/Include/core_cmFunc.h

+/**************************************************************************//**
+ * @file     core_cmFunc.h
+ * @brief    CMSIS Cortex-M Core Function Access Header File
+ * @version  V4.00
+ * @date     28. August 2014
+ *
+ * @note
+ *
+ ******************************************************************************/
+/* Copyright (c) 2009 - 2014 ARM LIMITED
+
+   All rights reserved.
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+   - Redistributions of source code must retain the above copyright
+     notice, this list of conditions and the following disclaimer.
+   - Redistributions in binary form must reproduce the above copyright
+     notice, this list of conditions and the following disclaimer in the
+     documentation and/or other materials provided with the distribution.
+   - Neither the name of ARM nor the names of its contributors may be used
+     to endorse or promote products derived from this software without
+     specific prior written permission.
+   *
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+   ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
+   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+   POSSIBILITY OF SUCH DAMAGE.
+   ---------------------------------------------------------------------------*/
+
+
+#ifndef __CORE_CMFUNC_H
+#define __CORE_CMFUNC_H
+
+
+/* ###########################  Core Function Access  ########################### */
+/** \ingroup  CMSIS_Core_FunctionInterface
+    \defgroup CMSIS_Core_RegAccFunctions CMSIS Core Register Access Functions
+  @{
+ */
+
+#if   defined ( __CC_ARM ) /*------------------RealView Compiler -----------------*/
+/* ARM armcc specific functions */
+
+#if (__ARMCC_VERSION < 400677)
+  #error "Please use ARM Compiler Toolchain V4.0.677 or later!"
+#endif
+
+/* intrinsic void __enable_irq();     */
+/* intrinsic void __disable_irq();    */
+
+/** \brief  Get Control Register
+
+    This function returns the content of the Control Register.
+
+    \return               Control Register value
+ */
+__STATIC_INLINE uint32_t __get_CONTROL(void)
+{
+  register uint32_t __regControl         __ASM("control");
+  return(__regControl);
+}
+
+
+/** \brief  Set Control Register
+
+    This function writes the given value to the Control Register.
+
+    \param [in]    control  Control Register value to set
+ */
+__STATIC_INLINE void __set_CONTROL(uint32_t control)
+{
+  register uint32_t __regControl         __ASM("control");
+  __regControl = control;
+}
+
+
+/** \brief  Get IPSR Register
+
+    This function returns the content of the IPSR Register.
+
+    \return               IPSR Register value
+ */
+__STATIC_INLINE uint32_t __get_IPSR(void)
+{
+  register uint32_t __regIPSR          __ASM("ipsr");
+  return(__regIPSR);
+}
+
+
+/** \brief  Get APSR Register
+
+    This function returns the content of the APSR Register.
+
+    \return               APSR Register value
+ */
+__STATIC_INLINE uint32_t __get_APSR(void)
+{
+  register uint32_t __regAPSR          __ASM("apsr");
+  return(__regAPSR);
+}
+
+
+/** \brief  Get xPSR Register
+
+    This function returns the content of the xPSR Register.
+
+    \return               xPSR Register value
+ */
+__STATIC_INLINE uint32_t __get_xPSR(void)
+{
+  register uint32_t __regXPSR          __ASM("xpsr");
+  return(__regXPSR);
+}
+
+
+/** \brief  Get Process Stack Pointer
+
+    This function returns the current value of the Process Stack Pointer (PSP).
+
+    \return               PSP Register value
+ */
+__STATIC_INLINE uint32_t __get_PSP(void)
+{
+  register uint32_t __regProcessStackPointer  __ASM("psp");
+  return(__regProcessStackPointer);
+}
+
+
+/** \brief  Set Process Stack Pointer
+
+    This function assigns the given value to the Process Stack Pointer (PSP).
+
+    \param [in]    topOfProcStack  Process Stack Pointer value to set
+ */
+__STATIC_INLINE void __set_PSP(uint32_t topOfProcStack)
+{
+  register uint32_t __regProcessStackPointer  __ASM("psp");
+  __regProcessStackPointer = topOfProcStack;
+}
+
+
+/** \brief  Get Main Stack Pointer
+
+    This function returns the current value of the Main Stack Pointer (MSP).
+
+    \return               MSP Register value
+ */
+__STATIC_INLINE uint32_t __get_MSP(void)
+{
+  register uint32_t __regMainStackPointer     __ASM("msp");
+  return(__regMainStackPointer);
+}
+
+
+/** \brief  Set Main Stack Pointer
+
+    This function assigns the given value to the Main Stack Pointer (MSP).
+
+    \param [in]    topOfMainStack  Main Stack Pointer value to set
+ */
+__STATIC_INLINE void __set_MSP(uint32_t topOfMainStack)
+{
+  register uint32_t __regMainStackPointer     __ASM("msp");
+  __regMainStackPointer = topOfMainStack;
+}
+
+
+/** \brief  Get Priority Mask
+
+    This function returns the current state of the priority mask bit from the Priority Mask Register.
+
+    \return               Priority Mask value
+ */
+__STATIC_INLINE uint32_t __get_PRIMASK(void)
+{
+  register uint32_t __regPriMask         __ASM("primask");
+  return(__regPriMask);
+}
+
+
+/** \brief  Set Priority Mask
+
+    This function assigns the given value to the Priority Mask Register.
+
+    \param [in]    priMask  Priority Mask
+ */
+__STATIC_INLINE void __set_PRIMASK(uint32_t priMask)
+{
+  register uint32_t __regPriMask         __ASM("primask");
+  __regPriMask = (priMask);
+}
+
+
+#if       (__CORTEX_M >= 0x03) || (__CORTEX_SC >= 300)
+
+/** \brief  Enable FIQ
+
+    This function enables FIQ interrupts by clearing the F-bit in the CPSR.
+    Can only be executed in Privileged modes.
+ */
+#define __enable_fault_irq                __enable_fiq
+
+
+/** \brief  Disable FIQ
+
+    This function disables FIQ interrupts by setting the F-bit in the CPSR.
+    Can only be executed in Privileged modes.
+ */
+#define __disable_fault_irq               __disable_fiq
+
+
+/** \brief  Get Base Priority
+
+    This function returns the current value of the Base Priority register.
+
+    \return               Base Priority register value
+ */
+__STATIC_INLINE uint32_t  __get_BASEPRI(void)
+{
+  register uint32_t __regBasePri         __ASM("basepri");
+  return(__regBasePri);
+}
+
+
+/** \brief  Set Base Priority
+
+    This function assigns the given value to the Base Priority register.
+
+    \param [in]    basePri  Base Priority value to set
+ */
+__STATIC_INLINE void __set_BASEPRI(uint32_t basePri)
+{
+  register uint32_t __regBasePri         __ASM("basepri");
+  __regBasePri = (basePri & 0xff);
+}
+
+
+/** \brief  Get Fault Mask
+
+    This function returns the current value of the Fault Mask register.
+
+    \return               Fault Mask register value
+ */
+__STATIC_INLINE uint32_t __get_FAULTMASK(void)
+{
+  register uint32_t __regFaultMask       __ASM("faultmask");
+  return(__regFaultMask);
+}
+
+
+/** \brief  Set Fault Mask
+
+    This function assigns the given value to the Fault Mask register.
+
+    \param [in]    faultMask  Fault Mask value to set
+ */
+__STATIC_INLINE void __set_FAULTMASK(uint32_t faultMask)
+{
+  register uint32_t __regFaultMask       __ASM("faultmask");
+  __regFaultMask = (faultMask & (uint32_t)1);
+}
+
+#endif /* (__CORTEX_M >= 0x03) || (__CORTEX_SC >= 300) */
+
+
+#if       (__CORTEX_M == 0x04) || (__CORTEX_M == 0x07)
+
+/** \brief  Get FPSCR
+
+    This function returns the current value of the Floating Point Status/Control register.
+
+    \return               Floating Point Status/Control register value
+ */
+__STATIC_INLINE uint32_t __get_FPSCR(void)
+{
+#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
+  register uint32_t __regfpscr         __ASM("fpscr");
+  return(__regfpscr);
+#else
+   return(0);
+#endif
+}
+
+
+/** \brief  Set FPSCR
+
+    This function assigns the given value to the Floating Point Status/Control register.
+
+    \param [in]    fpscr  Floating Point Status/Control value to set
+ */
+__STATIC_INLINE void __set_FPSCR(uint32_t fpscr)
+{
+#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
+  register uint32_t __regfpscr         __ASM("fpscr");
+  __regfpscr = (fpscr);
+#endif
+}
+
+#endif /* (__CORTEX_M == 0x04) || (__CORTEX_M == 0x07) */
+
+
+#elif defined ( __GNUC__ ) /*------------------ GNU Compiler ---------------------*/
+/* GNU gcc specific functions */
+
+/** \brief  Enable IRQ Interrupts
+
+  This function enables IRQ interrupts by clearing the I-bit in the CPSR.
+  Can only be executed in Privileged modes.
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __enable_irq(void)
+{
+  __ASM volatile ("cpsie i" : : : "memory");
+}
+
+
+/** \brief  Disable IRQ Interrupts
+
+  This function disables IRQ interrupts by setting the I-bit in the CPSR.
+  Can only be executed in Privileged modes.
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __disable_irq(void)
+{
+  __ASM volatile ("cpsid i" : : : "memory");
+}
+
+
+/** \brief  Get Control Register
+
+    This function returns the content of the Control Register.
+
+    \return               Control Register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_CONTROL(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, control" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Set Control Register
+
+    This function writes the given value to the Control Register.
+
+    \param [in]    control  Control Register value to set
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_CONTROL(uint32_t control)
+{
+  __ASM volatile ("MSR control, %0" : : "r" (control) : "memory");
+}
+
+
+/** \brief  Get IPSR Register
+
+    This function returns the content of the IPSR Register.
+
+    \return               IPSR Register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_IPSR(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, ipsr" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Get APSR Register
+
+    This function returns the content of the APSR Register.
+
+    \return               APSR Register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_APSR(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, apsr" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Get xPSR Register
+
+    This function returns the content of the xPSR Register.
+
+    \return               xPSR Register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_xPSR(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, xpsr" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Get Process Stack Pointer
+
+    This function returns the current value of the Process Stack Pointer (PSP).
+
+    \return               PSP Register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_PSP(void)
+{
+  register uint32_t result;
+
+  __ASM volatile ("MRS %0, psp\n"  : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Set Process Stack Pointer
+
+    This function assigns the given value to the Process Stack Pointer (PSP).
+
+    \param [in]    topOfProcStack  Process Stack Pointer value to set
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_PSP(uint32_t topOfProcStack)
+{
+  __ASM volatile ("MSR psp, %0\n" : : "r" (topOfProcStack) : "sp");
+}
+
+
+/** \brief  Get Main Stack Pointer
+
+    This function returns the current value of the Main Stack Pointer (MSP).
+
+    \return               MSP Register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_MSP(void)
+{
+  register uint32_t result;
+
+  __ASM volatile ("MRS %0, msp\n" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Set Main Stack Pointer
+
+    This function assigns the given value to the Main Stack Pointer (MSP).
+
+    \param [in]    topOfMainStack  Main Stack Pointer value to set
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_MSP(uint32_t topOfMainStack)
+{
+  __ASM volatile ("MSR msp, %0\n" : : "r" (topOfMainStack) : "sp");
+}
+
+
+/** \brief  Get Priority Mask
+
+    This function returns the current state of the priority mask bit from the Priority Mask Register.
+
+    \return               Priority Mask value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_PRIMASK(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, primask" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Set Priority Mask
+
+    This function assigns the given value to the Priority Mask Register.
+
+    \param [in]    priMask  Priority Mask
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_PRIMASK(uint32_t priMask)
+{
+  __ASM volatile ("MSR primask, %0" : : "r" (priMask) : "memory");
+}
+
+
+#if       (__CORTEX_M >= 0x03)
+
+/** \brief  Enable FIQ
+
+    This function enables FIQ interrupts by clearing the F-bit in the CPSR.
+    Can only be executed in Privileged modes.
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __enable_fault_irq(void)
+{
+  __ASM volatile ("cpsie f" : : : "memory");
+}
+
+
+/** \brief  Disable FIQ
+
+    This function disables FIQ interrupts by setting the F-bit in the CPSR.
+    Can only be executed in Privileged modes.
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __disable_fault_irq(void)
+{
+  __ASM volatile ("cpsid f" : : : "memory");
+}
+
+
+/** \brief  Get Base Priority
+
+    This function returns the current value of the Base Priority register.
+
+    \return               Base Priority register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_BASEPRI(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, basepri_max" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Set Base Priority
+
+    This function assigns the given value to the Base Priority register.
+
+    \param [in]    basePri  Base Priority value to set
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_BASEPRI(uint32_t value)
+{
+  __ASM volatile ("MSR basepri, %0" : : "r" (value) : "memory");
+}
+
+
+/** \brief  Get Fault Mask
+
+    This function returns the current value of the Fault Mask register.
+
+    \return               Fault Mask register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_FAULTMASK(void)
+{
+  uint32_t result;
+
+  __ASM volatile ("MRS %0, faultmask" : "=r" (result) );
+  return(result);
+}
+
+
+/** \brief  Set Fault Mask
+
+    This function assigns the given value to the Fault Mask register.
+
+    \param [in]    faultMask  Fault Mask value to set
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_FAULTMASK(uint32_t faultMask)
+{
+  __ASM volatile ("MSR faultmask, %0" : : "r" (faultMask) : "memory");
+}
+
+#endif /* (__CORTEX_M >= 0x03) */
+
+
+#if       (__CORTEX_M == 0x04) || (__CORTEX_M == 0x07)
+
+/** \brief  Get FPSCR
+
+    This function returns the current value of the Floating Point Status/Control register.
+
+    \return               Floating Point Status/Control register value
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE uint32_t __get_FPSCR(void)
+{
+#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
+  uint32_t result;
+
+  /* Empty asm statement works as a scheduling barrier */
+  __ASM volatile ("");
+  __ASM volatile ("VMRS %0, fpscr" : "=r" (result) );
+  __ASM volatile ("");
+  return(result);
+#else
+   return(0);
+#endif
+}
+
+
+/** \brief  Set FPSCR
+
+    This function assigns the given value to the Floating Point Status/Control register.
+
+    \param [in]    fpscr  Floating Point Status/Control value to set
+ */
+__attribute__( ( always_inline ) ) __STATIC_INLINE void __set_FPSCR(uint32_t fpscr)
+{
+#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
+  /* Empty asm statement works as a scheduling barrier */
+  __ASM volatile ("");
+  __ASM volatile ("VMSR fpscr, %0" : : "r" (fpscr) : "vfpcc");
+  __ASM volatile ("");
+#endif
+}
+
+#endif /* (__CORTEX_M == 0x04) || (__CORTEX_M == 0x07) */
+
+
+#elif defined ( __ICCARM__ ) /*------------------ ICC Compiler -------------------*/
+/* IAR iccarm specific functions */
+#include <cmsis_iar.h>
+
+
+#elif defined ( __TMS470__ ) /*---------------- TI CCS Compiler ------------------*/
+/* TI CCS specific functions */
+#include <cmsis_ccs.h>
+
+
+#elif defined ( __TASKING__ ) /*------------------ TASKING Compiler --------------*/
+/* TASKING carm specific functions */
+/*
+ * The CMSIS functions have been implemented as intrinsics in the compiler.
+ * Please use "carm -?i" to get an up to date list of all intrinsics,
+ * Including the CMSIS ones.
+ */
+
+
+#elif defined ( __CSMC__ ) /*------------------ COSMIC Compiler -------------------*/
+/* Cosmic specific functions */
+#include <cmsis_csm.h>
+
+#endif
+
+/*@} end of CMSIS_Core_RegAccFunctions */
+
+#endif /* __CORE_CMFUNC_H */

bsp/nrf51822/Libraries/SConscript

+import rtconfig
+Import('RTT_ROOT')
+from building import *
+
+# get current directory
+cwd = GetCurrentDir()
+
+# The set of source files associated with this SConscript file.
+src = Split("""
+nrf51822/Source/templates/system_nrf51.c
+""")
+
+#add for Startup script 
+if rtconfig.CROSS_TOOL == 'gcc':
+     src = src + ['nrf51822/Source/templates/arm/arm_startup_nrf51.s']
+elif rtconfig.CROSS_TOOL == 'keil':
+     src = src + ['nrf51822/Source/templates/arm/arm_startup_nrf51.s']
+elif rtconfig.CROSS_TOOL == 'iar':
+     src = src + ['nrf51822/Source/templates/arm/arm_startup_nrf51.s']
+
+path = [cwd + '/CMSIS/Include',
+        cwd + '/nrf51822/Include']
+
+CPPDEFINES = ['USE_STDPERIPH_DRIVER', 'NRF51']
+group = DefineGroup('Startup Code', src, depend = [''], CPPPATH = path, CPPDEFINES = CPPDEFINES)
+
+Return('group')

bsp/nrf51822/Libraries/nrf51822/Include/nrf_gpio.h

+#ifndef NRF_GPIO_H__
+#define NRF_GPIO_H__
+
+#include "nrf51.h"
+#include "nrf51_bitfields.h"
+
+/**
+ * @defgroup nrf_gpio GPIO abstraction
+ * @{
+ * @ingroup nrf_drivers
+ * @brief GPIO pin abstraction and port abstraction for reading and writing byte-wise to GPIO ports.
+ *
+ * Here, the GPIO ports are defined as follows:
+ * - Port 0 -> pin 0-7
+ * - Port 1 -> pin 8-15
+ * - Port 2 -> pin 16-23
+ * - Port 3 -> pin 24-31
+ */
+
+/**
+ * @enum nrf_gpio_port_dir_t
+ * @brief Enumerator used for setting the direction of a GPIO port.
+ */
+typedef enum
+{
+    NRF_GPIO_PORT_DIR_OUTPUT,       ///<  Output
+    NRF_GPIO_PORT_DIR_INPUT         ///<  Input
+} nrf_gpio_port_dir_t;
+
+/**
+ * @enum nrf_gpio_pin_dir_t
+ * Pin direction definitions.
+ */
+typedef enum
+{
+    NRF_GPIO_PIN_DIR_INPUT,   ///< Input
+    NRF_GPIO_PIN_DIR_OUTPUT   ///< Output
+} nrf_gpio_pin_dir_t;
+
+/**
+ * @enum nrf_gpio_port_select_t
+ * @brief Enumerator used for selecting between port 0 - 3.
+ */
+typedef enum
+{
+    NRF_GPIO_PORT_SELECT_PORT0 = 0,           ///<  Port 0 (GPIO pin 0-7)
+    NRF_GPIO_PORT_SELECT_PORT1,               ///<  Port 1 (GPIO pin 8-15)
+    NRF_GPIO_PORT_SELECT_PORT2,               ///<  Port 2 (GPIO pin 16-23)
+    NRF_GPIO_PORT_SELECT_PORT3,               ///<  Port 3 (GPIO pin 24-31)
+} nrf_gpio_port_select_t;
+
+/**
+ * @enum nrf_gpio_pin_pull_t
+ * @brief Enumerator used for selecting the pin to be pulled down or up at the time of pin configuration
+ */
+typedef enum
+{
+    NRF_GPIO_PIN_NOPULL   = GPIO_PIN_CNF_PULL_Disabled,                 ///<  Pin pullup resistor disabled
+    NRF_GPIO_PIN_PULLDOWN = GPIO_PIN_CNF_PULL_Pulldown,                 ///<  Pin pulldown resistor enabled
+    NRF_GPIO_PIN_PULLUP   = GPIO_PIN_CNF_PULL_Pullup,                   ///<  Pin pullup resistor enabled
+} nrf_gpio_pin_pull_t;
+
+/**
+ * @enum nrf_gpio_pin_sense_t
+ * @brief Enumerator used for selecting the pin to sense high or low level on the pin input.
+ */
+typedef enum
+{
+    NRF_GPIO_PIN_NOSENSE    = GPIO_PIN_CNF_SENSE_Disabled,              ///<  Pin sense level disabled.
+    NRF_GPIO_PIN_SENSE_LOW  = GPIO_PIN_CNF_SENSE_Low,                   ///<  Pin sense low level.
+    NRF_GPIO_PIN_SENSE_HIGH = GPIO_PIN_CNF_SENSE_High,                  ///<  Pin sense high level.
+} nrf_gpio_pin_sense_t;
+
+/**
+ * @brief Function for configuring the GPIO pin range as outputs with normal drive strength.
+ *        This function can be used to configure pin range as simple output with gate driving GPIO_PIN_CNF_DRIVE_S0S1 (normal cases).
+ *
+ * @param pin_range_start specifies the start number (inclusive) in the range of pin numbers to be configured (allowed values 0-30)
+ *
+ * @param pin_range_end specifies the end number (inclusive) in the range of pin numbers to be configured (allowed values 0-30)
+ *
+ * @note For configuring only one pin as output use @ref nrf_gpio_cfg_output
+ *       Sense capability on the pin is disabled, and input is disconnected from the buffer as the pins are configured as output.
+ */
+static __INLINE void nrf_gpio_range_cfg_output(uint32_t pin_range_start, uint32_t pin_range_end)
+{
+    /*lint -e{845} // A zero has been given as right argument to operator '|'" */
+    for (; pin_range_start <= pin_range_end; pin_range_start++)
+    {
+        NRF_GPIO->PIN_CNF[pin_range_start] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
+                                        | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
+                                        | (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos)
+                                        | (GPIO_PIN_CNF_INPUT_Disconnect << GPIO_PIN_CNF_INPUT_Pos)
+                                        | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
+    }
+}
+
+/**
+ * @brief Function for configuring the GPIO pin range as inputs with given initial value set, hiding inner details.
+ *        This function can be used to configure pin range as simple input.
+ *
+ * @param pin_range_start specifies the start number (inclusive) in the range of pin numbers to be configured (allowed values 0-30)
+ *
+ * @param pin_range_end specifies the end number (inclusive) in the range of pin numbers to be configured (allowed values 0-30)
+ *
+ * @param pull_config State of the pin range pull resistor (no pull, pulled down or pulled high)
+ *
+ * @note  For configuring only one pin as input use @ref nrf_gpio_cfg_input
+ *        Sense capability on the pin is disabled, and input is connected to buffer so that the GPIO->IN register is readable
+ */
+static __INLINE void nrf_gpio_range_cfg_input(uint32_t pin_range_start, uint32_t pin_range_end, nrf_gpio_pin_pull_t pull_config)
+{
+    /*lint -e{845} // A zero has been given as right argument to operator '|'" */
+    for (; pin_range_start <= pin_range_end; pin_range_start++)
+    {
+        NRF_GPIO->PIN_CNF[pin_range_start] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
+                                        | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
+                                        | (pull_config << GPIO_PIN_CNF_PULL_Pos)
+                                        | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)
+                                        | (GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos);
+    }
+}
+
+/**
+ * @brief Function for configuring the given GPIO pin number as output with given initial value set, hiding inner details.
+ *        This function can be used to configure pin range as simple input with gate driving GPIO_PIN_CNF_DRIVE_S0S1 (normal cases).
+ *
+ * @param pin_number specifies the pin number of gpio pin numbers to be configured (allowed values 0-30)
+ *
+ * @note  Sense capability on the pin is disabled, and input is disconnected from the buffer as the pins are configured as output.
+ */
+static __INLINE void nrf_gpio_cfg_output(uint32_t pin_number)
+{
+    /*lint -e{845} // A zero has been given as right argument to operator '|'" */
+    NRF_GPIO->PIN_CNF[pin_number] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
+                                            | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
+                                            | (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos)
+                                            | (GPIO_PIN_CNF_INPUT_Disconnect << GPIO_PIN_CNF_INPUT_Pos)
+                                            | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
+}
+
+/**
+ * @brief Function for configuring the given GPIO pin number as input with given initial value set, hiding inner details.
+ *        This function can be used to configure pin range as simple input with gate driving GPIO_PIN_CNF_DRIVE_S0S1 (normal cases).
+ *
+ * @param pin_number specifies the pin number of gpio pin numbers to be configured (allowed values 0-30)
+ *
+ * @param pull_config State of the pin range pull resistor (no pull, pulled down or pulled high)
+ *
+ * @note  Sense capability on the pin is disabled, and input is connected to buffer so that the GPIO->IN register is readable
+ */
+static __INLINE void nrf_gpio_cfg_input(uint32_t pin_number, nrf_gpio_pin_pull_t pull_config)
+{
+    /*lint -e{845} // A zero has been given as right argument to operator '|'" */
+    NRF_GPIO->PIN_CNF[pin_number] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
+                                        | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
+                                        | (pull_config << GPIO_PIN_CNF_PULL_Pos)
+                                        | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)
+                                        | (GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos);
+}
+
+/**
+ * @brief Function for configuring the given GPIO pin number as input with given initial value set, hiding inner details.
+ *        This function can be used to configure pin range as simple input with gate driving GPIO_PIN_CNF_DRIVE_S0S1 (normal cases).
+ *        Sense capability on the pin is configurable, and input is connected to buffer so that the GPIO->IN register is readable.
+ *
+ * @param pin_number specifies the pin number of gpio pin numbers to be configured (allowed values 0-30).
+ *
+ * @param pull_config state of the pin pull resistor (no pull, pulled down or pulled high).
+ *
+ * @param sense_config sense level of the pin (no sense, sense low or sense high).
+ */
+static __INLINE void nrf_gpio_cfg_sense_input(uint32_t pin_number, nrf_gpio_pin_pull_t pull_config, nrf_gpio_pin_sense_t sense_config)
+{
+    /*lint -e{845} // A zero has been given as right argument to operator '|'" */
+    NRF_GPIO->PIN_CNF[pin_number] = (sense_config << GPIO_PIN_CNF_SENSE_Pos)
+                                        | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
+                                        | (pull_config << GPIO_PIN_CNF_PULL_Pos)
+                                        | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)
+                                        | (GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos);
+}
+
+/**
+ * @brief Function for setting the direction for a GPIO pin.
+ *
+ * @param pin_number specifies the pin number [0:31] for which to
+ * set the direction.
+ *
+ * @param direction specifies the direction
+ */
+static __INLINE void nrf_gpio_pin_dir_set(uint32_t pin_number, nrf_gpio_pin_dir_t direction)
+{
+    if(direction == NRF_GPIO_PIN_DIR_INPUT)
+    {
+        NRF_GPIO->PIN_CNF[pin_number] =
+          (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
+        | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
+        | (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos)
+        | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)
+        | (GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos);
+    }
+    else
+    {
+        NRF_GPIO->DIRSET = (1UL << pin_number);
+    }
+}
+
+/**
+ * @brief Function for setting a GPIO pin.
+ *
+ * Note that the pin must be configured as an output for this
+ * function to have any effect.
+ *
+ * @param pin_number specifies the pin number [0:31] to
+ * set.
+ */
+static __INLINE void nrf_gpio_pin_set(uint32_t pin_number)
+{
+    NRF_GPIO->OUTSET = (1UL << pin_number);
+}
+
+/**
+ * @brief Function for clearing a GPIO pin.
+ *
+ * Note that the pin must be configured as an output for this
+ * function to have any effect.
+ *
+ * @param pin_number specifies the pin number [0:31] to
+ * clear.
+ */
+static __INLINE void nrf_gpio_pin_clear(uint32_t pin_number)
+{
+    NRF_GPIO->OUTCLR = (1UL << pin_number);
+}
+
+/**
+ * @brief Function for toggling a GPIO pin.
+ *
+ * Note that the pin must be configured as an output for this
+ * function to have any effect.
+ *
+ * @param pin_number specifies the pin number [0:31] to
+ * toggle.
+ */
+static __INLINE void nrf_gpio_pin_toggle(uint32_t pin_number)
+{
+    const uint32_t pin_bit   = 1UL << pin_number;
+    const uint32_t pin_state = ((NRF_GPIO->OUT >> pin_number) & 1UL);
+    
+    if (pin_state == 0)
+    {
+        // Current state low, set high.
+        NRF_GPIO->OUTSET = pin_bit;        
+    }
+    else
+    {
+        // Current state high, set low.    
+        NRF_GPIO->OUTCLR = pin_bit;       
+    }
+}
+
+/**
+ * @brief Function for writing a value to a GPIO pin.
+ *
+ * Note that the pin must be configured as an output for this
+ * function to have any effect.
+ *
+ * @param pin_number specifies the pin number [0:31] to
+ * write.
+ *
+ * @param value specifies the value to be written to the pin.
+ * @arg 0 clears the pin
+ * @arg >=1 sets the pin.
+ */
+static __INLINE void nrf_gpio_pin_write(uint32_t pin_number, uint32_t value)
+{
+    if (value == 0)
+    {
+        nrf_gpio_pin_clear(pin_number);
+    }
+    else
+    {
+        nrf_gpio_pin_set(pin_number);
+    }
+}
+
+/**
+ * @brief Function for reading the input level of a GPIO pin.
+ *
+ * Note that the pin must have input connected for the value
+ * returned from this function to be valid.
+ *
+ * @param pin_number specifies the pin number [0:31] to
+ * read.
+ *
+ * @return
+ * @retval 0 if the pin input level is low.
+ * @retval 1 if the pin input level is high.
+ * @retval > 1 should never occur.
+ */
+static __INLINE uint32_t nrf_gpio_pin_read(uint32_t pin_number)
+{
+    return  ((NRF_GPIO->IN >> pin_number) & 1UL);
+}
+
+/**
+ * @brief Generic function for writing a single byte of a 32 bit word at a given
+ * address.
+ *
+ * This function should not be called from outside the nrf_gpio
+ * abstraction layer.
+ *
+ * @param word_address is the address of the word to be written.
+ *
+ * @param byte_no is the the word byte number (0-3) to be written.
+ *
+ * @param value is the value to be written to byte "byte_no" of word
+ * at address "word_address"
+ */
+static __INLINE void nrf_gpio_word_byte_write(volatile uint32_t * word_address, uint8_t byte_no, uint8_t value)
+{
+    *((volatile uint8_t*)(word_address) + byte_no) = value;
+}
+
+/**
+ * @brief Generic function for reading a single byte of a 32 bit word at a given
+ * address.
+ *
+ * This function should not be called from outside the nrf_gpio
+ * abstraction layer.
+ *
+ * @param word_address is the address of the word to be read.
+ *
+ * @param byte_no is the the byte number (0-3) of the word to be read.
+ *
+ * @return byte "byte_no" of word at address "word_address".
+ */
+static __INLINE uint8_t nrf_gpio_word_byte_read(const volatile uint32_t* word_address, uint8_t byte_no)
+{
+    return (*((const volatile uint8_t*)(word_address) + byte_no));
+}
+
+/**
+ * @brief Function for setting the direction of a port.
+ *
+ * @param port is the port for which to set the direction.
+ *
+ * @param dir direction to be set for this port.
+ */
+static __INLINE void nrf_gpio_port_dir_set(nrf_gpio_port_select_t port, nrf_gpio_port_dir_t dir)
+{
+    if (dir == NRF_GPIO_PORT_DIR_OUTPUT)
+    {
+        nrf_gpio_word_byte_write(&NRF_GPIO->DIRSET, port, 0xFF);
+    }
+    else
+    {
+        nrf_gpio_range_cfg_input(port*8, (port+1)*8-1, NRF_GPIO_PIN_NOPULL);
+    }
+}
+
+/**
+ * @brief Function for reading a GPIO port.
+ *
+ * @param port is the port to read.
+ *
+ * @return the input value on this port.
+ */
+static __INLINE uint8_t nrf_gpio_port_read(nrf_gpio_port_select_t port)
+{
+    return nrf_gpio_word_byte_read(&NRF_GPIO->IN, port);
+}
+
+/**
+ * @brief Function for writing to a GPIO port.
+ *
+ * @param port is the port to write.
+ *
+ * @param value is the value to write to this port.
+ *
+ * @sa nrf_gpio_port_dir_set()
+ */
+static __INLINE void nrf_gpio_port_write(nrf_gpio_port_select_t port, uint8_t value)
+{
+    nrf_gpio_word_byte_write(&NRF_GPIO->OUT, port, value);
+}
+
+/**
+ * @brief Function for setting individual pins on GPIO port.
+ *
+ * @param port is the port for which to set the pins.
+ *
+ * @param set_mask is a mask specifying which pins to set. A bit
+ * set to 1 indicates that the corresponding port pin shall be
+ * set.
+ *
+ * @sa nrf_gpio_port_dir_set()
+ */
+static __INLINE void nrf_gpio_port_set(nrf_gpio_port_select_t port, uint8_t set_mask)
+{
+    nrf_gpio_word_byte_write(&NRF_GPIO->OUTSET, port, set_mask);
+}
+
+/**
+ * @brief Function for clearing individual pins on GPIO port.
+ *
+ * @param port is the port for which to clear the pins.
+ *
+ * @param clr_mask is a mask specifying which pins to clear. A bit
+ * set to 1 indicates that the corresponding port pin shall be
+ * cleared.
+ *
+ * @sa nrf_gpio_port_dir_set()
+ */
+static __INLINE void nrf_gpio_port_clear(nrf_gpio_port_select_t port, uint8_t clr_mask)
+{
+    nrf_gpio_word_byte_write(&NRF_GPIO->OUTCLR, port, clr_mask);
+}
+
+/** @} */
+
+#endif

bsp/nrf51822/Libraries/nrf51822/Include/system_nrf51.h

+/* Copyright (c) 2013, Nordic Semiconductor ASA
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice, this
+ *     list of conditions and the following disclaimer.
+ *
+ *   * Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *
+ *   * Neither the name of Nordic Semiconductor ASA nor the names of its
+ *     contributors may be used to endorse or promote products derived from
+ *     this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+#ifndef SYSTEM_NRF51_H
+#define SYSTEM_NRF51_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+
+extern uint32_t SystemCoreClock;    /*!< System Clock Frequency (Core Clock)  */
+
+/**
+ * Initialize the system
+ *
+ * @param  none
+ * @return none
+ *
+ * @brief  Setup the microcontroller system.
+ *         Initialize the System and update the SystemCoreClock variable.
+ */
+extern void SystemInit (void);
+
+/**
+ * Update SystemCoreClock variable
+ *
+ * @param  none
+ * @return none
+ *
+ * @brief  Updates the SystemCoreClock with current core Clock 
+ *         retrieved from cpu registers.
+ */
+extern void SystemCoreClockUpdate (void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* SYSTEM_NRF51_H */

bsp/nrf51822/Libraries/nrf51822/Source/templates/arm/arm_startup_nrf51.s

+; Copyright (c) 2013, Nordic Semiconductor ASA
+; All rights reserved.
+; 
+; Redistribution and use in source and binary forms, with or without
+; modification, are permitted provided that the following conditions are met:
+; 
+; * Redistributions of source code must retain the above copyright notice, this
+;   list of conditions and the following disclaimer.
+; 
+; * Redistributions in binary form must reproduce the above copyright notice,
+;   this list of conditions and the following disclaimer in the documentation
+;   and/or other materials provided with the distribution.
+; 
+; * Neither the name of Nordic Semiconductor ASA nor the names of its
+;   contributors may be used to endorse or promote products derived from
+;   this software without specific prior written permission.
+; 
+; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+; AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+; IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+; DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+; FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+; DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+; SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+; CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+; OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+; OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ 
+; NOTE: Template files (including this one) are application specific and therefore 
+; expected to be copied into the application project folder prior to its use!
+
+; Description message
+
+Stack_Size      EQU     0x00000400
+                AREA    STACK, NOINIT, READWRITE, ALIGN=3
+Stack_Mem       SPACE   Stack_Size
+__initial_sp
+
+Heap_Size       EQU     0x00000000
+
+                AREA    HEAP, NOINIT, READWRITE, ALIGN=3
+__heap_base
+Heap_Mem        SPACE   Heap_Size
+__heap_limit
+
+                PRESERVE8
+                THUMB
+
+; Vector Table Mapped to Address 0 at Reset
+
+                AREA    RESET, DATA, READONLY
+                EXPORT  __Vectors
+                EXPORT  __Vectors_End
+                EXPORT  __Vectors_Size
+
+__Vectors       DCD     __initial_sp              ; Top of Stack
+                DCD     Reset_Handler             ; Reset Handler
+                DCD     NMI_Handler               ; NMI Handler
+                DCD     HardFault_Handler         ; Hard Fault Handler
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     SVC_Handler               ; SVCall Handler
+                DCD     0                         ; Reserved
+                DCD     0                         ; Reserved
+                DCD     PendSV_Handler            ; PendSV Handler
+                DCD     SysTick_Handler           ; SysTick Handler
+
+                ; External Interrupts
+                DCD      POWER_CLOCK_IRQHandler ;POWER_CLOCK
+                DCD      RADIO_IRQHandler ;RADIO
+                DCD      UART0_IRQHandler ;UART0
+                DCD      SPI0_TWI0_IRQHandler ;SPI0_TWI0
+                DCD      SPI1_TWI1_IRQHandler ;SPI1_TWI1
+                DCD      0 ;Reserved
+                DCD      GPIOTE_IRQHandler ;GPIOTE
+                DCD      ADC_IRQHandler ;ADC
+                DCD      TIMER0_IRQHandler ;TIMER0
+                DCD      TIMER1_IRQHandler ;TIMER1
+                DCD      TIMER2_IRQHandler ;TIMER2
+                DCD      RTC0_IRQHandler ;RTC0
+                DCD      TEMP_IRQHandler ;TEMP
+                DCD      RNG_IRQHandler ;RNG
+                DCD      ECB_IRQHandler ;ECB
+                DCD      CCM_AAR_IRQHandler ;CCM_AAR
+                DCD      WDT_IRQHandler ;WDT
+                DCD      RTC1_IRQHandler ;RTC1
+                DCD      QDEC_IRQHandler ;QDEC
+                DCD      LPCOMP_IRQHandler ;LPCOMP
+                DCD      SWI0_IRQHandler ;SWI0
+                DCD      SWI1_IRQHandler ;SWI1
+                DCD      SWI2_IRQHandler ;SWI2
+                DCD      SWI3_IRQHandler ;SWI3
+                DCD      SWI4_IRQHandler ;SWI4
+                DCD      SWI5_IRQHandler ;SWI5
+                DCD      0 ;Reserved
+                DCD      0 ;Reserved
+                DCD      0 ;Reserved
+                DCD      0 ;Reserved
+                DCD      0 ;Reserved
+                DCD      0 ;Reserved
+
+
+__Vectors_End
+
+__Vectors_Size  EQU     __Vectors_End - __Vectors
+
+                AREA    |.text|, CODE, READONLY
+
+; Reset Handler
+
+NRF_POWER_RAMON_ADDRESS            EQU   0x40000524  ; NRF_POWER->RAMON address
+NRF_POWER_RAMONB_ADDRESS           EQU   0x40000554  ; NRF_POWER->RAMONB address
+NRF_POWER_RAMONx_RAMxON_ONMODE_Msk EQU   0x3         ; All RAM blocks on in onmode bit mask
+
+Reset_Handler   PROC
+                EXPORT  Reset_Handler             [WEAK]
+                IMPORT  SystemInit
+                IMPORT  __main
+                
+                MOVS    R1, #NRF_POWER_RAMONx_RAMxON_ONMODE_Msk
+                
+                LDR     R0, =NRF_POWER_RAMON_ADDRESS
+                LDR     R2, [R0]
+                ORRS    R2, R2, R1
+                STR     R2, [R0]
+                
+                LDR     R0, =NRF_POWER_RAMONB_ADDRESS
+                LDR     R2, [R0]
+                ORRS    R2, R2, R1
+                STR     R2, [R0]
+                
+                LDR     R0, =SystemInit
+                BLX     R0
+                LDR     R0, =__main
+                BX      R0
+                ENDP
+
+; Dummy Exception Handlers (infinite loops which can be modified)
+
+NMI_Handler     PROC
+                EXPORT  NMI_Handler               [WEAK]
+                B       .
+                ENDP
+HardFault_Handler\
+                PROC
+                EXPORT  HardFault_Handler         [WEAK]
+                B       .
+                ENDP
+SVC_Handler     PROC
+                EXPORT  SVC_Handler               [WEAK]
+                B       .
+                ENDP
+PendSV_Handler  PROC
+                EXPORT  PendSV_Handler            [WEAK]
+                B       .
+                ENDP
+SysTick_Handler PROC
+                EXPORT  SysTick_Handler           [WEAK]
+                B       .
+                ENDP
+
+Default_Handler PROC
+
+                EXPORT   POWER_CLOCK_IRQHandler [WEAK]
+                EXPORT   RADIO_IRQHandler [WEAK]
+                EXPORT   UART0_IRQHandler [WEAK]
+                EXPORT   SPI0_TWI0_IRQHandler [WEAK]
+                EXPORT   SPI1_TWI1_IRQHandler [WEAK]
+                EXPORT   GPIOTE_IRQHandler [WEAK]
+                EXPORT   ADC_IRQHandler [WEAK]
+                EXPORT   TIMER0_IRQHandler [WEAK]
+                EXPORT   TIMER1_IRQHandler [WEAK]
+                EXPORT   TIMER2_IRQHandler [WEAK]
+                EXPORT   RTC0_IRQHandler [WEAK]
+                EXPORT   TEMP_IRQHandler [WEAK]
+                EXPORT   RNG_IRQHandler [WEAK]
+                EXPORT   ECB_IRQHandler [WEAK]
+                EXPORT   CCM_AAR_IRQHandler [WEAK]
+                EXPORT   WDT_IRQHandler [WEAK]
+                EXPORT   RTC1_IRQHandler [WEAK]
+                EXPORT   QDEC_IRQHandler [WEAK]
+                EXPORT   LPCOMP_IRQHandler [WEAK]
+                EXPORT   SWI0_IRQHandler [WEAK]
+                EXPORT   SWI1_IRQHandler [WEAK]
+                EXPORT   SWI2_IRQHandler [WEAK]
+                EXPORT   SWI3_IRQHandler [WEAK]
+                EXPORT   SWI4_IRQHandler [WEAK]
+                EXPORT   SWI5_IRQHandler [WEAK]
+POWER_CLOCK_IRQHandler
+RADIO_IRQHandler
+UART0_IRQHandler
+SPI0_TWI0_IRQHandler
+SPI1_TWI1_IRQHandler
+GPIOTE_IRQHandler
+ADC_IRQHandler
+TIMER0_IRQHandler
+TIMER1_IRQHandler
+TIMER2_IRQHandler
+RTC0_IRQHandler
+TEMP_IRQHandler
+RNG_IRQHandler
+ECB_IRQHandler
+CCM_AAR_IRQHandler
+WDT_IRQHandler
+RTC1_IRQHandler
+QDEC_IRQHandler
+LPCOMP_IRQHandler
+SWI0_IRQHandler
+SWI1_IRQHandler
+SWI2_IRQHandler
+SWI3_IRQHandler
+SWI4_IRQHandler
+SWI5_IRQHandler
+
+                B .
+                ENDP
+                ALIGN
+
+; User Initial Stack & Heap
+
+                IF      :DEF:__MICROLIB
+                
+                EXPORT  __initial_sp
+                EXPORT  __heap_base
+                EXPORT  __heap_limit
+
+                ELSE
+
+                IMPORT  __use_two_region_memory
+                EXPORT  __user_initial_stackheap
+__user_initial_stackheap
+
+                LDR     R0, = Heap_Mem
+                LDR     R1, = (Stack_Mem + Stack_Size)
+                LDR     R2, = (Heap_Mem + Heap_Size)
+                LDR     R3, = Stack_Mem
+                BX      LR
+
+                ALIGN
+
+                ENDIF
+
+                END
+

bsp/nrf51822/Libraries/nrf51822/Source/templates/system_nrf51.c

+/* Copyright (c) 2013, Nordic Semiconductor ASA
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice, this
+ *     list of conditions and the following disclaimer.
+ *
+ *   * Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *
+ *   * Neither the name of Nordic Semiconductor ASA nor the names of its
+ *     contributors may be used to endorse or promote products derived from
+ *     this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+/* NOTE: Template files (including this one) are application specific and therefore expected to 
+   be copied into the application project folder prior to its use! */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "nrf.h"
+#include "system_nrf51.h"
+
+/*lint ++flb "Enter library region" */
+
+
+#define __SYSTEM_CLOCK      (16000000UL)     /*!< nRF51 devices use a fixed System Clock Frequency of 16MHz */
+
+static bool is_manual_peripheral_setup_needed(void);
+static bool is_disabled_in_debug_needed(void);
+
+
+#if defined ( __CC_ARM )
+    uint32_t SystemCoreClock __attribute__((used)) = __SYSTEM_CLOCK;  
+#elif defined ( __ICCARM__ )
+    __root uint32_t SystemCoreClock = __SYSTEM_CLOCK;
+#elif defined   ( __GNUC__ )
+    uint32_t SystemCoreClock __attribute__((used)) = __SYSTEM_CLOCK;
+#endif
+
+void SystemCoreClockUpdate(void)
+{
+    SystemCoreClock = __SYSTEM_CLOCK;
+}
+
+void SystemInit(void)
+{
+    /* If desired, switch off the unused RAM to lower consumption by the use of RAMON register.
+       It can also be done in the application main() function. */
+
+    /* Prepare the peripherals for use as indicated by the PAN 26 "System: Manual setup is required
+       to enable the use of peripherals" found at Product Anomaly document for your device found at
+       https://www.nordicsemi.com/. The side effect of executing these instructions in the devices 
+       that do not need it is that the new peripherals in the second generation devices (LPCOMP for
+       example) will not be available. */
+    if (is_manual_peripheral_setup_needed())
+    {
+        *(uint32_t volatile *)0x40000504 = 0xC007FFDF;
+        *(uint32_t volatile *)0x40006C18 = 0x00008000;
+    }
+    
+    /* Disable PROTENSET registers under debug, as indicated by PAN 59 "MPU: Reset value of DISABLEINDEBUG
+       register is incorrect" found at Product Anomaly document four your device found at 
+       https://www.nordicsemi.com/. There is no side effect of using these instruction if not needed. */
+    if (is_disabled_in_debug_needed())
+    {
+        NRF_MPU->DISABLEINDEBUG = MPU_DISABLEINDEBUG_DISABLEINDEBUG_Disabled << MPU_DISABLEINDEBUG_DISABLEINDEBUG_Pos;
+    }
+}
+
+
+static bool is_manual_peripheral_setup_needed(void) 
+{
+    if ((((*(uint32_t *)0xF0000FE0) & 0x000000FF) == 0x1) && (((*(uint32_t *)0xF0000FE4) & 0x0000000F) == 0x0))
+    {
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x00) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x10) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x30) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+    }
+    
+    return false;
+}
+
+static bool is_disabled_in_debug_needed(void) 
+{
+    if ((((*(uint32_t *)0xF0000FE0) & 0x000000FF) == 0x1) && (((*(uint32_t *)0xF0000FE4) & 0x0000000F) == 0x0))
+    {
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x40) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+    }
+    
+    return false;
+}
+
+/*lint --flb "Leave library region" */

bsp/nrf51822/SConscript

+# for module compiling
+import os
+from building import *
+
+cwd  = GetCurrentDir()
+objs = []
+list = os.listdir(cwd)
+
+for d in list:
+    path = os.path.join(cwd, d)
+    if os.path.isfile(os.path.join(path, 'SConscript')):
+        objs = objs + SConscript(os.path.join(d, 'SConscript'))
+
+Return('objs')

bsp/nrf51822/SConstruct

+import os
+import sys
+import rtconfig
+
+if os.getenv('RTT_ROOT'):
+    RTT_ROOT = os.getenv('RTT_ROOT')
+else:
+    RTT_ROOT = os.path.normpath(os.getcwd() + '/../..')
+
+sys.path = sys.path + [os.path.join(RTT_ROOT, 'tools')]
+from building import *
+
+TARGET = 'rtthread-stm32f0xx.' + rtconfig.TARGET_EXT
+
+env = Environment(tools = ['mingw'],
+	AS = rtconfig.AS, ASFLAGS = rtconfig.AFLAGS,
+	CC = rtconfig.CC, CCFLAGS = rtconfig.CFLAGS,
+	AR = rtconfig.AR, ARFLAGS = '-rc',
+	LINK = rtconfig.LINK, LINKFLAGS = rtconfig.LFLAGS)
+env.PrependENVPath('PATH', rtconfig.EXEC_PATH)
+
+if rtconfig.PLATFORM == 'iar':
+	env.Replace(CCCOM = ['$CC $CCFLAGS $CPPFLAGS $_CPPDEFFLAGS $_CPPINCFLAGS -o $TARGET $SOURCES'])
+	env.Replace(ARFLAGS = [''])
+	env.Replace(LINKCOM = ['$LINK $SOURCES $LINKFLAGS -o $TARGET --map project.map'])
+
+Export('RTT_ROOT')
+Export('rtconfig')
+
+# prepare building environment
+objs = PrepareBuilding(env, RTT_ROOT, has_libcpu=False)
+
+# make a building
+DoBuilding(TARGET, objs)

bsp/nrf51822/applications/SConscript

+Import('RTT_ROOT')
+Import('rtconfig')
+from building import *
+
+cwd     = os.path.join(str(Dir('#')), 'applications')
+src	= Glob('*.c')
+CPPPATH = [cwd, str(Dir('#'))]
+
+group = DefineGroup('Applications', src, depend = [''], CPPPATH = CPPPATH)
+
+Return('group')

bsp/nrf51822/applications/application.c

+/*
+ * File      : application.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2015-03-01     Yangfs       the first version
+ * 2015-03-27     Bernard      code cleanup.
+ */
+
+/**
+ * @addtogroup NRF51822
+ */
+/*@{*/
+
+#include <rtthread.h>
+
+#ifdef RT_USING_FINSH
+#include <finsh.h>
+#include <shell.h>
+#endif
+
+int rt_application_init(void)
+{
+    /* Set finsh device */
+#ifdef RT_USING_FINSH
+    /* initialize finsh */
+    finsh_system_init();
+#endif
+    return 0;
+}
+
+
+/*@}*/

bsp/nrf51822/applications/startup.c

+/*
+ * File      : startup.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Develop Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://openlab.rt-thread.com/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2015-03-01     Yangfs       the first version
+ * 2015-03-27     Bernard      code cleanup.
+ */
+
+#include <rthw.h>
+#include <rtthread.h>
+
+#include "board.h"
+
+/**
+ * @addtogroup NRF51822
+ */
+
+/*@{*/
+
+extern int  rt_application_init(void);
+
+#ifdef __CC_ARM
+extern int Image$$RW_IRAM1$$ZI$$Limit;
+#define NRF_SRAM_BEGIN    (&Image$$RW_IRAM1$$ZI$$Limit)
+#elif __ICCARM__
+#pragma section="HEAP"
+#define NRF_SRAM_BEGIN    (__segment_end("HEAP"))
+#else
+extern int __bss_end;
+#define NRF_SRAM_BEGIN    (&__bss_end)
+#endif
+
+/**
+ * This function will startup RT-Thread RTOS.
+ */
+void rtthread_startup(void)
+{
+    /* init board */
+    rt_hw_board_init();
+
+    /* show version */
+    rt_show_version();
+
+    /* init tick */
+    rt_system_tick_init();
+
+    /* init kernel object */
+    rt_system_object_init();
+
+    /* init timer system */
+    rt_system_timer_init();
+
+#ifdef RT_USING_HEAP
+    rt_system_heap_init((void*)NRF_SRAM_BEGIN, (void*)NRF_SRAM_END);
+#endif
+
+    /* init scheduler system */
+    rt_system_scheduler_init();
+
+    /* init application */
+    rt_application_init();
+
+    /* init timer thread */
+    rt_system_timer_thread_init();
+
+    /* init idle thread */
+    rt_thread_idle_init();
+
+    /* start scheduler */
+    rt_system_scheduler_start();
+
+    /* never reach here */
+    return ;
+}
+
+int main(void)
+{
+    /* disable interrupt first */
+    rt_hw_interrupt_disable();
+
+    /* startup RT-Thread RTOS */
+    rtthread_startup();
+
+    return 0;
+}
+
+/*@}*/

bsp/nrf51822/drivers/SConscript

+Import('RTT_ROOT')
+Import('rtconfig')
+from building import *
+
+# get current directory
+cwd = GetCurrentDir()
+
+src	= Glob('*.c')
+CPPPATH = [cwd]
+
+group = DefineGroup('Drivers', src, depend = [''], CPPPATH = CPPPATH)
+
+Return('group')

bsp/nrf51822/drivers/board.c

+/*
+ * File      : board.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2009 RT-Thread Develop Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ */
+
+#include <rthw.h>
+#include <rtthread.h>
+
+#include <nrf51.h>
+#include <nrf51_bitfields.h>
+
+#include "board.h"
+#include "uart.h"
+
+/**
+ * @addtogroup NRF51822
+ */
+
+/*@{*/
+#define LFCLK_FREQUENCY           (32768UL)                                 /**< LFCLK frequency in Hertz, constant. */
+#define RTC_FREQUENCY             (800UL)                                   /**< Required RTC working clock RTC_FREQUENCY Hertz. Changable. */
+#define COUNTER_PRESCALER         ((LFCLK_FREQUENCY / RTC_FREQUENCY) - 1)   /* f = LFCLK/(prescaler + 1) */
+
+
+/** @brief Function starting the internal LFCLK XTAL oscillator.
+ */
+void lfclk_config(void)
+{
+    NRF_CLOCK->LFCLKSRC            = (CLOCK_LFCLKSRC_SRC_Xtal << CLOCK_LFCLKSRC_SRC_Pos);
+    NRF_CLOCK->EVENTS_LFCLKSTARTED = 0;
+    NRF_CLOCK->TASKS_LFCLKSTART    = 1;
+    while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0)
+    {
+        //Do nothing.
+    }
+    NRF_CLOCK->EVENTS_LFCLKSTARTED = 0;
+}
+
+
+/** @brief Function for configuring the RTC with TICK to 100Hz.
+ */
+void rtc_config(void)
+{
+    NVIC_EnableIRQ(RTC0_IRQn);                 // Enable Interrupt for the RTC in the core.
+    NRF_RTC0->PRESCALER = COUNTER_PRESCALER;   // Set prescaler to a TICK of RTC_FREQUENCY.
+
+    // Enable TICK event and TICK interrupt:
+    NRF_RTC0->EVTENSET = RTC_EVTENSET_TICK_Msk;
+    NRF_RTC0->INTENSET = RTC_INTENSET_TICK_Msk;
+}
+
+
+/** @brief: Function for handling the RTC0 interrupts.
+ * Triggered on TICK and COMPARE0 match.
+ */
+void RTC0_IRQHandler(void)
+{
+    /* enter interrupt */
+    rt_interrupt_enter();
+    if ((NRF_RTC0->EVENTS_TICK != 0) &&
+            ((NRF_RTC0->INTENSET & RTC_INTENSET_TICK_Msk) != 0))
+    {
+        NRF_RTC0->EVENTS_TICK = 0;
+
+        rt_tick_increase();  //This function will notify kernel there is one tick passed
+    }
+    /* leave interrupt */
+    rt_interrupt_leave();
+}
+
+
+/**
+ * This function will initial NRF51822 board.
+ */
+void rt_hw_board_init()
+{
+    lfclk_config();
+    rtc_config();
+    NRF_RTC0->TASKS_START = 1;
+    /* Initial usart deriver, and set console device */
+    rt_hw_uart_init();
+
+#ifdef RT_USING_CONSOLE
+    rt_console_set_device(RT_CONSOLE_DEVICE_NAME);
+#endif
+}
+
+/*@}*/

bsp/nrf51822/drivers/board.h

+/*
+ * File      : board.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2009, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ */
+
+#ifndef __BOARD_H__
+#define __BOARD_H__
+
+
+
+void rt_hw_board_init(void);
+
+#endif

bsp/nrf51822/drivers/uart.c

+/*
+ * File      : uart.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015 RT-Thread Develop Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <rthw.h>
+#include <rtdevice.h>
+
+#include "board.h"
+#include "uart.h"
+
+#include <nrf_gpio.h>
+
+#define UART_RX_BUFSZ 512
+rt_uint8_t rx_buffer[UART_RX_BUFSZ];
+
+struct nrf51822_uart
+{
+    struct rt_device parent;
+    struct rt_ringbuffer rx_rb;
+} uart_device;
+
+void UART0_IRQHandler(void)
+{
+    rt_ubase_t level;
+    struct nrf51822_uart* uart = &uart_device;
+
+    level = rt_hw_interrupt_disable();
+
+    // Wait for RXD data to be received
+    while (NRF_UART0->EVENTS_RXDRDY != 1) ;
+    NRF_UART0->EVENTS_RXDRDY = 0;
+
+    rt_hw_interrupt_enable(level);
+    /* [Handling the data received over UART] */
+    rt_ringbuffer_putchar_force(&(uart->rx_rb), (rt_uint8_t)NRF_UART0->RXD);
+
+    /* invoke callback */
+    if(uart->parent.rx_indicate != RT_NULL)
+    {
+        uart->parent.rx_indicate(&uart->parent, rt_ringbuffer_data_len(&uart->rx_rb));
+    }
+}
+
+
+static rt_err_t rt_uart_init (rt_device_t dev)
+{
+    /* UART Initialization and Enable */
+    /** @snippet [Configure UART RX and TX pin] */
+    nrf_gpio_cfg_output(TX_PIN_NUMBER);
+    nrf_gpio_cfg_input(RX_PIN_NUMBER, NRF_GPIO_PIN_NOPULL);
+
+    NRF_UART0->PSELTXD = TX_PIN_NUMBER;
+    NRF_UART0->PSELRXD = RX_PIN_NUMBER;
+    /** @snippet [Configure UART RX and TX pin] */
+    if (HWFC)
+    {
+        nrf_gpio_cfg_output(RTS_PIN_NUMBER);
+        nrf_gpio_cfg_input(CTS_PIN_NUMBER, NRF_GPIO_PIN_NOPULL);
+        NRF_UART0->PSELCTS = CTS_PIN_NUMBER;
+        NRF_UART0->PSELRTS = RTS_PIN_NUMBER;
+        NRF_UART0->CONFIG  = (UART_CONFIG_HWFC_Enabled << UART_CONFIG_HWFC_Pos);
+    }
+
+    NRF_UART0->BAUDRATE      = (UART_BAUDRATE_BAUDRATE_Baud38400 << UART_BAUDRATE_BAUDRATE_Pos);
+    NRF_UART0->ENABLE        = (UART_ENABLE_ENABLE_Enabled << UART_ENABLE_ENABLE_Pos);
+    NRF_UART0->TASKS_STARTTX = 1;
+    NRF_UART0->TASKS_STARTRX = 1;
+    NRF_UART0->EVENTS_RXDRDY = 0;
+
+    NRF_UART0->INTENSET = (UART_INTENSET_RXDRDY_Enabled << UART_INTENSET_RXDRDY_Pos);
+
+    NVIC_EnableIRQ(UART0_IRQn);
+
+    return RT_EOK;
+}
+
+static rt_err_t rt_uart_open(rt_device_t dev, rt_uint16_t oflag)
+{
+    RT_ASSERT(dev != RT_NULL);
+    if (dev->flag & RT_DEVICE_FLAG_INT_RX)
+    {
+        /* Enable the UART Interrupt */
+        NVIC_EnableIRQ(UART0_IRQn);
+    }
+
+    return RT_EOK;
+}
+
+static rt_err_t rt_uart_close(rt_device_t dev)
+{
+    RT_ASSERT(dev != RT_NULL);
+    if (dev->flag & RT_DEVICE_FLAG_INT_RX)
+    {
+        /* Disable the UART Interrupt */
+        NVIC_DisableIRQ(UART0_IRQn);
+    }
+
+    return RT_EOK;
+}
+
+static rt_size_t rt_uart_read(rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+{
+    rt_size_t length;
+    struct nrf51822_uart *uart = (struct nrf51822_uart*)dev;
+    /* interrupt receive */
+    rt_base_t level;
+
+    RT_ASSERT(uart != RT_NULL);
+
+    /* disable interrupt */
+    level = rt_hw_interrupt_disable();
+    length = rt_ringbuffer_get(&(uart->rx_rb), buffer, size);
+    /* enable interrupt */
+    rt_hw_interrupt_enable(level);
+
+    return length;
+}
+
+static rt_size_t rt_uart_write(rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+{
+    char *ptr;
+    ptr = (char*) buffer;
+
+    if (dev->open_flag & RT_DEVICE_FLAG_STREAM)
+    {
+        /* stream mode */
+        while (size)
+        {
+            if (*ptr == '\n')
+            {
+                NRF_UART0->TXD = (uint8_t)'\r';
+
+                // Wait for TXD data to be sent.
+                while (NRF_UART0->EVENTS_TXDRDY != 1) ;
+
+                NRF_UART0->EVENTS_TXDRDY = 0;
+            }
+
+            NRF_UART0->TXD = (uint8_t)(*ptr);
+
+            // Wait for TXD data to be sent.
+            while (NRF_UART0->EVENTS_TXDRDY != 1) ;
+
+            NRF_UART0->EVENTS_TXDRDY = 0;
+
+            ptr ++;
+            size --;
+        }
+    }
+    else
+    {
+        while ( size != 0 )
+        {
+            NRF_UART0->TXD = (uint8_t)(*ptr);
+
+            // Wait for TXD data to be sent.
+            while (NRF_UART0->EVENTS_TXDRDY != 1) ;
+
+            NRF_UART0->EVENTS_TXDRDY = 0;
+
+            ptr++;
+            size--;
+        }
+    }
+
+    return (rt_size_t) ptr - (rt_size_t) buffer;
+}
+
+void rt_hw_uart_init(void)
+{
+    struct nrf51822_uart* uart;
+
+    /* get uart device */
+    uart = &uart_device;
+
+    /* device initialization */
+    uart->parent.type = RT_Device_Class_Char;
+    rt_ringbuffer_init(&(uart->rx_rb), rx_buffer, sizeof(rx_buffer));
+
+    /* device interface */
+    uart->parent.init 	    = rt_uart_init;
+    uart->parent.open 	    = rt_uart_open;
+    uart->parent.close      = rt_uart_close;
+    uart->parent.read 	    = rt_uart_read;
+    uart->parent.write      = rt_uart_write;
+    uart->parent.control    = RT_NULL;
+    uart->parent.user_data  = RT_NULL;
+
+    rt_device_register(&uart->parent, "uart0", RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX);
+}

bsp/nrf51822/drivers/uart.h

+/*
+ * File      : uart.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ */
+
+#ifndef __UART_H__
+#define __UART_H__
+
+
+
+#define RX_PIN_NUMBER          23
+#define TX_PIN_NUMBER          24
+#define CTS_PIN_NUMBER         25
+#define RTS_PIN_NUMBER         22
+#define HWFC                   false
+
+
+void rt_hw_uart_init(void);
+
+#endif

bsp/nrf51822/rtconfig.h

+/* RT-Thread config file */
+#ifndef __RTTHREAD_CFG_H__
+#define __RTTHREAD_CFG_H__
+
+/* RT_NAME_MAX*/
+#define RT_NAME_MAX	   6
+
+/* RT_ALIGN_SIZE*/
+#define RT_ALIGN_SIZE	4
+
+/* PRIORITY_MAX */
+#define RT_THREAD_PRIORITY_MAX	8
+
+/* Tick per Second */
+#define RT_TICK_PER_SECOND	100
+
+/* SECTION: RT_DEBUG */
+/* Thread Debug */
+#define RT_DEBUG
+//#define RT_DEBUG_INIT 1
+#define RT_USING_OVERFLOW_CHECK
+
+/* Using Hook */
+#define RT_USING_HOOK
+
+#define IDLE_THREAD_STACK_SIZE	512
+
+/* Using Software Timer */
+/* #define RT_USING_TIMER_SOFT */
+#define RT_TIMER_THREAD_PRIO		4
+#define RT_TIMER_THREAD_STACK_SIZE	512
+#define RT_TIMER_TICK_PER_SECOND	100
+
+/* SECTION: IPC */
+/* Using Semaphore*/
+#define RT_USING_SEMAPHORE
+
+/* Using Mutex */
+/* #define RT_USING_MUTEX */
+
+/* Using Event */
+/* #define RT_USING_EVENT */
+
+/* Using MailBox */
+#define RT_USING_MAILBOX
+
+/* Using Message Queue */
+/* #define RT_USING_MESSAGEQUEUE */
+
+/* SECTION: Memory Management */
+/* Using Memory Pool Management*/
+/* #define RT_USING_MEMPOOL */
+
+/* Using Dynamic Heap Management */
+//#define RT_USING_HEAP
+
+/* Using Small MM */
+#define RT_USING_SMALL_MEM
+#define RT_USING_TINY_SIZE
+
+// <bool name="RT_USING_COMPONENTS_INIT" description="Using RT-Thread components initialization" default="true" />
+//#define RT_USING_COMPONENTS_INIT
+
+/* SECTION: Device System */
+/* Using Device System */
+#define RT_USING_DEVICE
+// <bool name="RT_USING_DEVICE_IPC" description="Using device communication" default="true" />
+#define RT_USING_DEVICE_IPC
+// <bool name="RT_USING_SERIAL" description="Using Serial" default="true" />
+//#define RT_USING_SERIAL
+
+/* SECTION: Console options */
+#define RT_USING_CONSOLE
+/* the buffer size of console*/
+#define RT_CONSOLEBUF_SIZE	128
+// <string name="RT_CONSOLE_DEVICE_NAME" description="The device name for console" default="uart1" />
+#define RT_CONSOLE_DEVICE_NAME	    "uart0"
+
+
+
+/* SECTION: finsh, a C-Express shell */
+#define RT_USING_FINSH
+/* configure finsh parameters */
+#define FINSH_THREAD_PRIORITY 6
+#define FINSH_THREAD_STACK_SIZE	512
+#define FINSH_HISTORY_LINES	1
+/* Using symbol table */
+#define FINSH_USING_SYMTAB
+#define FINSH_USING_DESCRIPTION
+
+#define FINSH_USING_MSH
+#define FINSH_USING_MSH_ONLY
+
+#endif