/**
  ******************************************************************************
  * @file      startup_stm32l051xx.s
  * @author    MCD Application Team
  * @brief     STM32L051xx Devices vector table for GCC toolchain.
  *            This module performs:
  *                - Set the initial SP
  *                - Set the initial PC == Reset_Handler,
  *                - Set the vector table entries with the exceptions ISR address
  *                - Branches to main in the C library (which eventually
  *                  calls main()).
  *            After Reset the Cortex-M0+ processor is in Thread mode,
  *            priority is Privileged, and the Stack is set to Main.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2016 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */

  .syntax unified
  .cpu cortex-m0plus
  .fpu softvfp
  .thumb

.global  g_pfnVectors
.global  Default_Handler

/* start address for the initialization values of the .data section.
defined in linker script */
.word  _sidata
/* start address for the .data section. defined in linker script */
.word  _sdata
/* end address for the .data section. defined in linker script */
.word  _edata
/* start address for the .bss section. defined in linker script */
.word  _sbss
/* end address for the .bss section. defined in linker script */
.word  _ebss

    .section  .text.Reset_Handler
  .weak  Reset_Handler
  .type  Reset_Handler, %function
Reset_Handler:  
   ldr   r0, =_estack
   mov   sp, r0          /* set stack pointer */

/* Call the clock system initialization function.*/
  bl  SystemInit
  
/* Copy the data segment initializers from flash to SRAM */
  ldr r0, =_sdata
  ldr r1, =_edata
  ldr r2, =_sidata
  movs r3, #0
  b LoopCopyDataInit

CopyDataInit:
  ldr r4, [r2, r3]
  str r4, [r0, r3]
  adds r3, r3, #4

LoopCopyDataInit:
  adds r4, r0, r3
  cmp r4, r1
  bcc CopyDataInit
  
/* Zero fill the bss segment. */
  ldr r2, =_sbss
  ldr r4, =_ebss
  movs r3, #0
  b LoopFillZerobss

FillZerobss:
  str  r3, [r2]
  adds r2, r2, #4

LoopFillZerobss:
  cmp r2, r4
  bcc FillZerobss

/* Call static constructors */
    bl __libc_init_array
/* Call the application's entry point.*/
  bl  main

LoopForever:
    b LoopForever


.size  Reset_Handler, .-Reset_Handler

/**
 * @brief  This is the code that gets called when the processor receives an
 *         unexpected interrupt.  This simply enters an infinite loop, preserving
 *         the system state for examination by a debugger.
 *
 * @param  None
 * @retval : None
*/
    .section  .text.Default_Handler,"ax",%progbits
Default_Handler:
Infinite_Loop:
  b  Infinite_Loop
  .size  Default_Handler, .-Default_Handler
/******************************************************************************
*
* The minimal vector table for a Cortex M0.  Note that the proper constructs
* must be placed on this to ensure that it ends up at physical address
* 0x0000.0000.
*
******************************************************************************/
   .section  .isr_vector,"a",%progbits
  .type  g_pfnVectors, %object
  .size  g_pfnVectors, .-g_pfnVectors


g_pfnVectors:
  .word  _estack
  .word  Reset_Handler
  .word  NMI_Handler
  .word  HardFault_Handler
  .word  0
  .word  0
  .word  0
  .word  0
  .word  0
  .word  0
  .word  0
  .word  SVC_Handler
  .word  0         
  .word  0
  .word  PendSV_Handler
  .word  SysTick_Handler
  .word  WWDG_IRQHandler                   /* Window WatchDog              */
  .word  PVD_IRQHandler                    /* PVD through EXTI Line detection */
  .word  RTC_IRQHandler                    /* RTC through the EXTI line     */
  .word  FLASH_IRQHandler                  /* FLASH                        */
  .word  RCC_IRQHandler                    /* RCC                          */
  .word  EXTI0_1_IRQHandler                /* EXTI Line 0 and 1            */
  .word  EXTI2_3_IRQHandler                /* EXTI Line 2 and 3            */
  .word  EXTI4_15_IRQHandler               /* EXTI Line 4 to 15            */
  .word  0                                 /* Reserved                     */
  .word  DMA1_Channel1_IRQHandler          /* DMA1 Channel 1               */
  .word  DMA1_Channel2_3_IRQHandler        /* DMA1 Channel 2 and Channel 3 */
  .word  DMA1_Channel4_5_6_7_IRQHandler    /* DMA1 Channel 4, Channel 5, Channel 6 and Channel 7*/
  .word  ADC1_COMP_IRQHandler              /* ADC1, COMP1 and COMP2        */
  .word  LPTIM1_IRQHandler                 /* LPTIM1                       */
  .word  0                                 /* Reserved                     */
  .word  TIM2_IRQHandler                   /* TIM2                         */
  .word  0                                 /* Reserved                     */
  .word  TIM6_IRQHandler                   /* TIM6                         */
  .word  0               				           /* Reserved                     */
  .word  0              					          /* Reserved                     */
  .word  TIM21_IRQHandler                  /* TIM21                        */
  .word  0                                 /* Reserved                     */
  .word  TIM22_IRQHandler                  /* TIM22                        */
  .word  I2C1_IRQHandler                   /* I2C1                         */
  .word  I2C2_IRQHandler                   /* I2C2                         */
  .word  SPI1_IRQHandler                   /* SPI1                         */
  .word  SPI2_IRQHandler                   /* SPI2                         */
  .word  USART1_IRQHandler                 /* USART1                       */
  .word  USART2_IRQHandler                 /* USART2                       */
  .word  LPUART1_IRQHandler                /* LPUART1                      */
  .word  0                                 /* Reserved                     */
  .word  0                                 /* Reserved                     */

/*******************************************************************************
*
* Provide weak aliases for each Exception handler to the Default_Handler.
* As they are weak aliases, any function with the same name will override
* this definition.
*
*******************************************************************************/

   .weak      NMI_Handler
   .thumb_set NMI_Handler,Default_Handler

   .weak      HardFault_Handler
   .thumb_set HardFault_Handler,Default_Handler

   .weak      SVC_Handler
   .thumb_set SVC_Handler,Default_Handler

   .weak      PendSV_Handler
   .thumb_set PendSV_Handler,Default_Handler

   .weak      SysTick_Handler
   .thumb_set SysTick_Handler,Default_Handler

   .weak      WWDG_IRQHandler
   .thumb_set WWDG_IRQHandler,Default_Handler

   .weak      PVD_IRQHandler
   .thumb_set PVD_IRQHandler,Default_Handler

   .weak      RTC_IRQHandler
   .thumb_set RTC_IRQHandler,Default_Handler

   .weak      FLASH_IRQHandler
   .thumb_set FLASH_IRQHandler,Default_Handler

   .weak      RCC_IRQHandler
   .thumb_set RCC_IRQHandler,Default_Handler

   .weak      EXTI0_1_IRQHandler
   .thumb_set EXTI0_1_IRQHandler,Default_Handler

   .weak      EXTI2_3_IRQHandler
   .thumb_set EXTI2_3_IRQHandler,Default_Handler

   .weak      EXTI4_15_IRQHandler
   .thumb_set EXTI4_15_IRQHandler,Default_Handler

   .weak      DMA1_Channel1_IRQHandler
   .thumb_set DMA1_Channel1_IRQHandler,Default_Handler

   .weak      DMA1_Channel2_3_IRQHandler
   .thumb_set DMA1_Channel2_3_IRQHandler,Default_Handler

   .weak      DMA1_Channel4_5_6_7_IRQHandler
   .thumb_set DMA1_Channel4_5_6_7_IRQHandler,Default_Handler

   .weak      ADC1_COMP_IRQHandler
   .thumb_set ADC1_COMP_IRQHandler,Default_Handler

   .weak      LPTIM1_IRQHandler
   .thumb_set LPTIM1_IRQHandler,Default_Handler

   .weak      TIM2_IRQHandler
   .thumb_set TIM2_IRQHandler,Default_Handler

   .weak      TIM6_IRQHandler
   .thumb_set TIM6_IRQHandler,Default_Handler

   .weak      TIM21_IRQHandler
   .thumb_set TIM21_IRQHandler,Default_Handler

   .weak      TIM22_IRQHandler
   .thumb_set TIM22_IRQHandler,Default_Handler

   .weak      I2C1_IRQHandler
   .thumb_set I2C1_IRQHandler,Default_Handler

   .weak      I2C2_IRQHandler
   .thumb_set I2C2_IRQHandler,Default_Handler

   .weak      SPI1_IRQHandler
   .thumb_set SPI1_IRQHandler,Default_Handler

   .weak      SPI2_IRQHandler
   .thumb_set SPI2_IRQHandler,Default_Handler

   .weak      USART1_IRQHandler
   .thumb_set USART1_IRQHandler,Default_Handler

   .weak      USART2_IRQHandler
   .thumb_set USART2_IRQHandler,Default_Handler

   .weak      LPUART1_IRQHandler
   .thumb_set LPUART1_IRQHandler,Default_Handler