Minimal viable Arduino core for the nRF52DK -> Blink works

Note: compiler.path and openocd.path are not generalized yet.

boards.txt

+# Copyright (c) 2014-2015 Arduino LLC.  All right reserved.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+nRF52DK.name=nRF52 DK
+
+nRF52DK.vid.0=0x1366
+nRF52DK.pid.0=0x1015
+
+nRF52DK.upload.tool=Nordic:openocd
+nRF52DK.upload.protocol=jlink
+nRF52DK.upload.setup_command=transport select swd
+nRF52DK.upload.use_1200bps_touch=false
+nRF52DK.upload.wait_for_upload_port=false
+nRF52DK.upload.native_usb=false
+nRF52DK.build.mcu=cortex-m4
+nRF52DK.build.f_cpu=16000000
+nRF52DK.build.board=NRF52_DK
+nRF52DK.build.core=nRF52
+nRF52DK.build.variant=nRF52DK
+nRF52DK.build.variant_system_lib=
+nRF52DK.build.extra_flags=-DGLAH
+nRF52DK.build.ldscript=linker_scripts/gcc/nRF52DK.ld

cores/nRF52/Arduino.h

+#ifndef Arduino_h
+#define Arduino_h
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+typedef bool boolean;
+typedef uint8_t byte;
+typedef uint16_t word;
+
+// some libraries and sketches depend on this AVR stuff,
+// assuming Arduino.h or WProgram.h automatically includes it...
+//
+// #include "avr/pgmspace.h"
+// #include "avr/interrupt.h"
+
+// #include "binary.h"
+// #include "itoa.h"
+
+#ifdef __cplusplus
+extern "C"{
+#endif // __cplusplus
+
+// Include Atmel headers
+// // #include "sam.h"
+
+#include "wiring_constants.h"
+
+// #define clockCyclesPerMicrosecond() ( SystemCoreClock / 1000000L )
+// #define clockCyclesToMicroseconds(a) ( ((a) * 1000L) / (SystemCoreClock / 1000L) )
+// #define microsecondsToClockCycles(a) ( (a) * (SystemCoreClock / 1000000L) )
+
+void yield( void ) ;
+
+/* sketch */
+void setup( void ) ;
+void loop( void ) ;
+
+// #include "WVariant.h"
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+// The following headers are for C++ only compilation
+#ifdef __cplusplus
+  // #include "WCharacter.h"
+  // #include "WString.h"
+  // #include "Tone.h"
+  // #include "WMath.h"
+  // #include "HardwareSerial.h"
+  // #include "pulse.h"
+#endif
+#include "delay.h"
+#ifdef __cplusplus
+  // #include "Uart.h"
+#endif
+
+// Include board variant
+#include "variant.h"
+
+#include "wiring.h"
+#include "wiring_digital.h"
+// #include "wiring_analog.h"
+// #include "wiring_shift.h"
+// #include "WInterrupts.h"
+
+// undefine stdlib's abs if encountered
+#ifdef abs
+#undef abs
+#endif // abs
+
+#define min(a,b) ((a)<(b)?(a):(b))
+#define max(a,b) ((a)>(b)?(a):(b))
+#define abs(x) ((x)>0?(x):-(x))
+#define constrain(amt,low,high) ((amt)<(low)?(low):((amt)>(high)?(high):(amt)))
+#define round(x)     ((x)>=0?(long)((x)+0.5):(long)((x)-0.5))
+#define radians(deg) ((deg)*DEG_TO_RAD)
+#define degrees(rad) ((rad)*RAD_TO_DEG)
+#define sq(x) ((x)*(x))
+
+#define interrupts() __enable_irq()
+#define noInterrupts() __disable_irq()
+
+#define lowByte(w) ((uint8_t) ((w) & 0xff))
+#define highByte(w) ((uint8_t) ((w) >> 8))
+
+#define bitRead(value, bit) (((value) >> (bit)) & 0x01)
+#define bitSet(value, bit) ((value) |= (1UL << (bit)))
+#define bitClear(value, bit) ((value) &= ~(1UL << (bit)))
+#define bitWrite(value, bit, bitvalue) (bitvalue ? bitSet(value, bit) : bitClear(value, bit))
+
+#define bit(b) (1UL << (b))
+
+#endif // Arduino_h

cores/nRF52/delay.c

+/*
+  Copyright (c) 2015 Arduino LLC.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include "nrf_gpio.h"
+
+#include "delay.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+uint32_t millis( void )
+{
+  return 0;
+}
+
+uint32_t micros( void )
+{
+  return 0;
+}
+
+void delay( uint32_t dwMs )
+{
+  nrf_delay_ms(dwMs);
+}
+
+void delayMicroseconds( uint32_t usec )
+{
+  nrf_delay_us(usec);
+}
+
+#ifdef __cplusplus
+}
+#endif

cores/nRF52/delay.h

+/*
+  Copyright (c) 2015 Arduino LLC.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef _DELAY_
+#define _DELAY_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+/**
+ * \brief Returns the number of milliseconds since the Arduino board began running the current program.
+ *
+ * This number will overflow (go back to zero), after approximately 50 days.
+ *
+ * \return Number of milliseconds since the program started (uint32_t)
+ */
+extern uint32_t millis( void ) ;
+
+/**
+ * \brief Returns the number of microseconds since the Arduino board began running the current program.
+ *
+ * This number will overflow (go back to zero), after approximately 70 minutes. On 16 MHz Arduino boards
+ * (e.g. Duemilanove and Nano), this function has a resolution of four microseconds (i.e. the value returned is
+ * always a multiple of four). On 8 MHz Arduino boards (e.g. the LilyPad), this function has a resolution
+ * of eight microseconds.
+ *
+ * \note There are 1,000 microseconds in a millisecond and 1,000,000 microseconds in a second.
+ */
+extern uint32_t micros( void ) ;
+
+/**
+ * \brief Pauses the program for the amount of time (in miliseconds) specified as parameter.
+ * (There are 1000 milliseconds in a second.)
+ *
+ * \param dwMs the number of milliseconds to pause (uint32_t)
+ */
+extern void delay( uint32_t dwMs ) ;
+
+/**
+ * \brief Pauses the program for the amount of time (in microseconds) specified as parameter.
+ *
+ * \param dwUs the number of microseconds to pause (uint32_t)
+ */
+extern void delayMicroseconds( uint32_t usec ) ;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _DELAY_ */

cores/nRF52/main.cpp

+/*
+  Copyright (c) 2015 Arduino LLC.  All right reserved.
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#define ARDUINO_MAIN
+#include "Arduino.h"
+
+// Weak empty variant initialization function.
+// May be redefined by variant files.
+void initVariant() __attribute__((weak));
+void initVariant() { }
+
+/*
+ * \brief Main entry point of Arduino application
+ */
+int main( void )
+{
+  init();
+
+  initVariant();
+
+  delay(1);
+
+  setup();
+
+  for (;;)
+  {
+    loop();
+  }
+
+  return 0;
+}

cores/nRF52/nRF52_SDK_0/components/device/compiler_abstraction.h

+/* Copyright (c) 2015, 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 _COMPILER_ABSTRACTION_H
+#define _COMPILER_ABSTRACTION_H
+
+/*lint ++flb "Enter library region" */
+
+#if defined ( __CC_ARM )
+    
+    #ifndef __ASM
+        #define __ASM               __asm                       
+    #endif
+    
+    #ifndef __INLINE
+        #define __INLINE            __inline                    
+    #endif
+    
+    #ifndef __WEAK
+        #define __WEAK              __weak                      
+    #endif
+    
+    #ifndef __ALIGN
+        #define __ALIGN(n)          __align(n)                  
+    #endif
+    
+    #define GET_SP()                __current_sp()              
+  
+#elif defined ( __ICCARM__ )
+    
+    #ifndef __ASM
+        #define __ASM               __asm                       
+    #endif
+    
+    #ifndef __INLINE
+        #define __INLINE            inline                      
+    #endif
+    
+    #ifndef __WEAK
+        #define __WEAK              __weak                      
+    #endif
+
+    /* Not defined for IAR since it requires a new line to work, and C preprocessor does not allow that. */
+    #ifndef __ALIGN
+        #define __ALIGN(n)          
+    #endif
+    
+    #define GET_SP()                __get_SP()                  
+    
+#elif defined   ( __GNUC__ )
+    
+    #ifndef __ASM
+        #define __ASM               __asm                       
+    #endif
+    
+    #ifndef __INLINE
+        #define __INLINE            inline                      
+    #endif
+    
+    #ifndef __WEAK
+        #define __WEAK              __attribute__((weak))       
+    #endif
+    
+    #ifndef __ALIGN
+        #define __ALIGN(n)          __attribute__((aligned(n))) 
+    #endif
+    
+    #define GET_SP()                gcc_current_sp()            
+
+    static inline unsigned int gcc_current_sp(void)
+    {
+        register unsigned sp __ASM("sp");
+        return sp;
+    }
+    
+#elif defined   ( __TASKING__ )
+        
+    #ifndef __ASM        
+        #define __ASM               __asm                      
+    #endif
+    
+    #ifndef __INLINE
+        #define __INLINE            inline                     
+    #endif
+    
+    #ifndef __WEAK
+        #define __WEAK              __attribute__((weak))      
+    #endif
+    
+    #ifndef __ALIGN
+        #define __ALIGN(n)          __align(n)                  
+    #endif
+    
+    #define GET_SP()                __get_MSP()                
+    
+#endif
+
+/*lint --flb "Leave library region" */
+
+#endif

cores/nRF52/nRF52_SDK_0/components/device/nrf.h

+/* Copyright (c) 2015, 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 NRF_H
+#define NRF_H
+
+#if defined(_WIN32)         
+    /* Do not include nrf51 specific files when building for PC host */
+#elif defined(__unix)       
+    /* Do not include nrf51 specific files when building for PC host */
+#elif defined(__APPLE__)    
+    /* Do not include nrf51 specific files when building for PC host */
+#else
+
+    /* Family selection for family includes. */
+    #if defined (NRF51)
+        #include "nrf51.h"
+        #include "nrf51_bitfields.h"
+        #include "nrf51_deprecated.h"
+    #elif defined (NRF52)
+        #include "nrf52.h"
+        #include "nrf52_bitfields.h"
+        #include "nrf51_to_nrf52.h"
+    #else
+        #error "Device family must be defined. See nrf.h."
+    #endif /* NRF51, NRF52 */
+
+    #include "compiler_abstraction.h"
+
+#endif /* _WIN32 || __unix || __APPLE__ */
+
+#endif /* NRF_H */
+

cores/nRF52/nRF52_SDK_0/components/drivers_nrf/delay/nrf_delay.c

+/* 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 <stdio.h>
+#include "compiler_abstraction.h"
+#include "nrf.h"
+#include "nrf_delay.h"
+
+/*lint --e{438} "Variable not used" */
+void nrf_delay_ms(uint32_t volatile number_of_ms)
+{
+    while(number_of_ms != 0)
+    {
+        number_of_ms--;
+        nrf_delay_us(999);
+    }
+}

cores/nRF52/nRF52_SDK_0/components/drivers_nrf/delay/nrf_delay.h

+#ifndef _NRF_DELAY_H
+#define _NRF_DELAY_H
+
+#include "nrf.h"
+
+/**
+ * @brief Function for delaying execution for number of microseconds.
+ *
+ * @note NRF52 has instruction cache and because of that delay is not precise.
+ *
+ * @param number_of_ms
+ */
+/*lint --e{438, 522} "Variable not used" "Function lacks side-effects" */
+#if defined ( __CC_ARM   )
+static __ASM void __INLINE nrf_delay_us(uint32_t volatile number_of_us)
+{
+loop
+        SUBS    R0, R0, #1
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+#ifdef NRF52
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+        NOP
+#endif
+        BNE    loop
+        BX     LR
+}
+#elif defined ( __ICCARM__ )
+static void __INLINE nrf_delay_us(uint32_t volatile number_of_us)
+{
+__ASM (
+"loop:\n\t"
+       " SUBS R0, R0, #1\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+       " NOP\n\t"
+#ifdef NRF52
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+        " NOP\n\t"
+#endif
+       " BNE loop\n\t");
+}
+#elif defined   (  __GNUC__  )
+static void __INLINE nrf_delay_us(uint32_t volatile number_of_us) __attribute__((always_inline));
+static void __INLINE nrf_delay_us(uint32_t volatile number_of_us)
+{
+register uint32_t delay asm ("r0") = number_of_us;
+__ASM volatile (
+#ifdef NRF51
+        ".syntax unified\n"
+#endif
+    "1:\n"
+    " SUBS %0, %0, #1\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"   
+    " NOP\n"  
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+#ifdef NRF52
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+    " NOP\n"
+#endif
+    " BNE 1b\n"
+#ifdef NRF51
+    ".syntax divided\n"
+#endif
+    : "+r" (delay));
+}
+#endif
+
+void nrf_delay_ms(uint32_t volatile number_of_ms);
+
+#endif

cores/nRF52/nRF52_SDK_0/components/toolchain/system_nrf52.c

+/* Copyright (c) 2015, 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.
+ *
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "nrf.h"
+#include "system_nrf52.h"
+
+/*lint ++flb "Enter library region" */
+
+#define __SYSTEM_CLOCK_16M      (16000000UL)     
+#define __SYSTEM_CLOCK_64M      (64000000UL)   
+
+static bool ftpan_32(void); 
+static bool ftpan_37(void); 
+static bool ftpan_36(void); 
+
+
+#if defined ( __CC_ARM )
+    uint32_t SystemCoreClock __attribute__((used)) = __SYSTEM_CLOCK_64M;
+#elif defined ( __ICCARM__ )
+    __root uint32_t SystemCoreClock = __SYSTEM_CLOCK_64M;
+#elif defined   ( __GNUC__ )
+    uint32_t SystemCoreClock __attribute__((used)) = __SYSTEM_CLOCK_64M;
+#endif
+
+void SystemCoreClockUpdate(void)
+{
+    SystemCoreClock = __SYSTEM_CLOCK_64M;
+}
+
+void SystemInit(void)
+{
+    /* Workaround for FTPAN-32 "DIF: Debug session automatically enables TracePort pins" found at Product Anomaly document 
+       for your device located at https://www.nordicsemi.com/ */
+    if (ftpan_32()){        
+        CoreDebug->DEMCR &= ~CoreDebug_DEMCR_TRCENA_Msk;
+    }
+    
+    /* Workaround for FTPAN-37 "AMLI: EasyDMA is slow with Radio, ECB, AAR and CCM." found at Product Anomaly document 
+       for your device located at https://www.nordicsemi.com/  */
+    if (ftpan_37()){        
+        *(volatile uint32_t *)0x400005A0 = 0x3;
+    }
+    
+    /* Workaround for FTPAN-36 "CLOCK: Some registers are not reset when expected." found at Product Anomaly document 
+       for your device located at https://www.nordicsemi.com/  */
+    if (ftpan_36()){        
+        NRF_CLOCK->EVENTS_DONE = 0;
+        NRF_CLOCK->EVENTS_CTTO = 0;
+    }
+
+    /* Enable the FPU if the compiler used floating point unit instructions. __FPU_USED is a MACRO defined by the 
+     * compiler. Since the FPU consumes energy, remember to disable FPU use in the compiler if floating point unit 
+     * operations are not used in your code. */
+    #if (__FPU_USED == 1)
+        SCB->CPACR |= (3UL << 20) | (3UL << 22); 
+        __DSB();
+        __ISB();
+    #endif
+    
+    /* Configure NFCT pins as GPIOs if NFCT is not to be used in your code. If CONFIG_NFCT_PINS_AS_GPIOS is not defined, 
+       two GPIOs (see Product Specification to see which ones) will be reserved for NFC and will not be available as 
+       normal GPIOs. */
+    #if defined (CONFIG_NFCT_PINS_AS_GPIOS)
+        if ((NRF_UICR->NFCPINS & UICR_NFCPINS_PROTECT_Msk) == (UICR_NFCPINS_PROTECT_NFC << UICR_NFCPINS_PROTECT_Pos)){
+            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}            
+            NRF_UICR->NFCPINS &= ~UICR_NFCPINS_PROTECT_Msk;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}            
+            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}            
+            NVIC_SystemReset();
+        }
+    #endif
+    
+    /* Configure GPIO pads as pPin Reset pin if Pin Reset capabilities desired. If CONFIG_GPIO_AS_PINRESET is not
+      defined, pin reset will not be available. One GPIO (see Product Specification to see which one) will then be 
+      reserved for PinReset and not available as normal GPIO. */
+    #if defined (CONFIG_GPIO_AS_PINRESET)
+        if (((NRF_UICR->PSELRESET[0] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos)) || 
+            ((NRF_UICR->PSELRESET[0] & UICR_PSELRESET_CONNECT_Msk) != (UICR_PSELRESET_CONNECT_Connected << UICR_PSELRESET_CONNECT_Pos))){
+            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Wen << NVMC_CONFIG_WEN_Pos;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
+            NRF_UICR->PSELRESET[0] = 21;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
+            NRF_UICR->PSELRESET[1] = 21;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
+            NRF_NVMC->CONFIG = NVMC_CONFIG_WEN_Ren << NVMC_CONFIG_WEN_Pos;
+            while (NRF_NVMC->READY == NVMC_READY_READY_Busy){}
+            NVIC_SystemReset();
+        }
+    #endif
+    
+    /* Enable SWO trace functionality. If ENABLE_SWO is not defined, SWO pin will be used as GPIO (see Product 
+       Specification to see which one). */
+    #if defined (ENABLE_SWO)
+        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
+        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Serial << CLOCK_TRACECONFIG_TRACEMUX_Pos;
+    #endif
+    
+    /* Enable Trace functionality. If ENABLE_TRACE is not defined, TRACE pins will be used as GPIOs (see Product 
+       Specification to see which ones). */
+    #if defined (ENABLE_TRACE)
+        CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
+        NRF_CLOCK->TRACECONFIG |= CLOCK_TRACECONFIG_TRACEMUX_Parallel << CLOCK_TRACECONFIG_TRACEMUX_Pos;
+    #endif
+
+    SystemCoreClockUpdate();
+}
+
+static bool ftpan_32(void)
+{
+    if ((((*(uint32_t *)0xF0000FE0) & 0x000000FF) == 0x6) && (((*(uint32_t *)0xF0000FE4) & 0x0000000F) == 0x0))
+    {
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x30) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+    }
+    
+    return false;
+}
+
+static bool ftpan_37(void)
+{
+    if ((((*(uint32_t *)0xF0000FE0) & 0x000000FF) == 0x6) && (((*(uint32_t *)0xF0000FE4) & 0x0000000F) == 0x0))
+    {
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x30) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+    }
+    
+    return false;
+}
+
+static bool ftpan_36(void)
+{
+    if ((((*(uint32_t *)0xF0000FE0) & 0x000000FF) == 0x6) && (((*(uint32_t *)0xF0000FE4) & 0x0000000F) == 0x0))
+    {
+        if ((((*(uint32_t *)0xF0000FE8) & 0x000000F0) == 0x30) && (((*(uint32_t *)0xF0000FEC) & 0x000000F0) == 0x0))
+        {
+            return true;
+        }
+    }
+    
+    return false;
+}
+
+
+
+/*lint --flb "Leave library region" */

cores/nRF52/nRF52_SDK_0/components/toolchain/system_nrf52.h

+/* Copyright (c) 2015, 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_NRF52_H
+#define SYSTEM_NRF52_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_NRF52_H */

cores/nRF52/wiring.c

+#include "wiring.h"
+
+void init( void )
+{
+}

cores/nRF52/wiring.h

+/*
+  Copyright (c) 2015 Arduino LLC.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern void init(void);
+
+#ifdef __cplusplus
+}
+#endif

cores/nRF52/wiring_constants.h

+/*
+  Copyright (c) 2014 Arduino.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef _WIRING_CONSTANTS_
+#define _WIRING_CONSTANTS_
+
+#ifdef __cplusplus
+extern "C"{
+#endif // __cplusplus
+
+#define LOW             (0x0)
+#define HIGH            (0x1)
+
+#define INPUT           (0x0)
+#define OUTPUT          (0x1)
+#define INPUT_PULLUP    (0x2)
+#define INPUT_PULLDOWN  (0x3)
+
+#define PI 3.1415926535897932384626433832795
+#define HALF_PI 1.5707963267948966192313216916398
+#define TWO_PI 6.283185307179586476925286766559
+#define DEG_TO_RAD 0.017453292519943295769236907684886
+#define RAD_TO_DEG 57.295779513082320876798154814105
+#define EULER 2.718281828459045235360287471352
+
+#define SERIAL  0x0
+#define DISPLAY 0x1
+
+enum BitOrder {
+	LSBFIRST = 0,
+	MSBFIRST = 1
+};
+
+// moved to WInterrupts.h
+////      LOW 0
+////      HIGH 1
+//#define CHANGE 2
+//#define FALLING 3
+//#define RISING 4
+//
+//#define DEFAULT 1
+//#define EXTERNAL 0
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus
+
+#endif /* _WIRING_CONSTANTS_ */

variants/nRF52DK/linker_scripts/gcc/nRF52DK.ld

+/* Linker script to configure memory regions. */
+
+SEARCH_DIR(.)
+GROUP(-lgcc -lc -lnosys)
+
+MEMORY
+{
+  FLASH (rx) : ORIGIN = 0x0, LENGTH = 0x80000
+  RAM (rwx) :  ORIGIN = 0x20000000, LENGTH = 0x8000
+}
+
+INCLUDE "nrf5x_common.ld"
\ No newline at end of file