.syntax unified
    .arch   armv6-m
    
    .extern main

    .section .stack
    .align  3
#ifdef __STACK_SIZE
    .equ    Stack_Size, __STACK_SIZE
#else
    .equ    Stack_Size, 0x600
#endif

    .globl  __StackTop
    .globl  __StackLimit
__StackLimit:
    .space  Stack_Size
    .size   __StackLimit, . - __StackLimit
__StackTop:
    .size   __StackTop, . - __StackTop

    .section .heap
    .align  3

    .equ    Heap_Size, 0

    .globl  __HeapBase
    .globl  __HeapLimit
__HeapBase:
    .if	Heap_Size
    .space  Heap_Size
    .endif
    .size   __HeapBase, . - __HeapBase
__HeapLimit:
    .size   __HeapLimit, . - __HeapLimit

    .section .isr_vector
    .align 2
    .globl  __isr_vector
__isr_vector:
        .long   __StackTop            /* Top of Stack */
        .long   Reset_Handler         /* Reset Handler */
        .long   NMI_Handler           /* NMI Handler */
        .long   HardFault_Handler     /* Hard Fault Handler */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   SVC_Handler           /* SVCall Handler */
        .long   0                     /* Reserved */
        .long   0                     /* Reserved */
        .long   PendSV_Handler        /* PendSV Handler */
        .long   SysTick_Handler       /* SysTick Handler */

        /* External interrupts */
        .long   EXTI_IRQHandler       /* 0 */
        .long   IWDT_IRQHandler       /* 1 */
        .long   BLE_IRQHandler        /* 2 */
        .long   DMAC_IRQHandler       /* 3 */
        .long   BB_LP_IRQHandler      /* 4 */
        .long   BTMR_IRQHandler       /* 5 */
        .long   CTMR1_IRQHandler      /* 6 */
        .long   ADMR1_IRQHandler      /* 7 */
        .long   RTC_IRQHandler        /* 8 */
        .long   I2C1_IRQHandler       /* 9 */
        .long   SPIM_IRQHandler       /* 10*/
        .long   SPIS_IRQHandler       /* 11 */
        .long   UART1_IRQHandler      /* 12 */
        .long   UART2_IRQHandler      /* 13 */
        .long   AON_PMU_IRQHandler    /* 14 */
        .long   LVD33_IRQHandler      /* 15 */
        .long   BOD12_IRQHandler      /* 16 */
        .long   USB_IRQHandler        /* 17 */
        .long   USB_SOF_IRQHandler    /* 18 */
        .long   FSHC_IRQHandler       /* 19 */
        .long   0                     /* 20 Reserved*/
        .long   0                     /* 21 Reserved*/
        .long   0                     /* 22 Reserved*/
        .long   0                     /* 23 Reserved*/
        .long   0                     /* 24 Reserved*/
        .long   0                     /* 25 Reserved*/
        .long   0                     /* 26 Reserved*/
        .long   0                     /* 27 Reserved*/
        .long   0                     /* 28 Reserved*/
        .long   0                     /* 29 Reserved*/
        .long   0                     /* 30 Reserved*/
        .long   0                     /* 31 Reserved*/
    .size	__isr_vector, . - __isr_vector


    .text
    .thumb
    .thumb_func
    .align	1
    .globl	Reset_Handler
    .type	Reset_Handler, %function
    .section ".text.user_irq_handler"
Reset_Handler:
    ldr	r1, =__etext
    ldr	r2, =__data_start__
    ldr	r3, =__data_end__


    subs	r3, r2
    ble	.L_loop1_done

.L_loop1:
    subs	r3, #4
    ldr	r0, [r1,r3]
    str	r0, [r2,r3]
    bgt	.L_loop1

.L_loop1_done:



/*  Single BSS section scheme.
 *
 *  The BSS section is specified by following symbols
 *    __bss_start__: start of the BSS section.
 *    __bss_end__: end of the BSS section.
 *
 *  Both addresses must be aligned to 4 bytes boundary.
 */
    ldr r1, =__bss_start__
    ldr r2, =__bss_end__

    movs r0, 0

    subs r2, r1
    ble	.L_loop3_done
    
.L_loop3:
    subs	r2, #4
    str	r0, [r1, r2]
    bgt	.L_loop3
    
.L_loop3_done:
    bl	main
    
    .pool
    .size	Reset_Handler, . - Reset_Handler

/* Dummy Exception Handlers (infinite loops which can be modified) */

    .weak   NMI_Handler
    .type   NMI_Handler, %function
NMI_Handler:
    b       .
    .size   NMI_Handler, . - NMI_Handler


    .weak   HardFault_Handler
    .type   HardFault_Handler, %function
HardFault_Handler:
    b       .
    .size   HardFault_Handler, . - HardFault_Handler


    .weak   SVC_Handler
    .type   SVC_Handler, %function
SVC_Handler:
    b       .
    .size   SVC_Handler, . - SVC_Handler


    .weak   PendSV_Handler
    .type   PendSV_Handler, %function
PendSV_Handler:
    b       .
    .size   PendSV_Handler, . - PendSV_Handler


    .weak   SysTick_Handler
    .type   SysTick_Handler, %function
SysTick_Handler:
    b       .
    .size   SysTick_Handler, . - SysTick_Handler
    
    .globl  Default_Handler
    .type	Default_Handler, %function
Default_Handler:
    b       .
    .size	Default_Handler, . - Default_Handler

/*    Macro to define default handlers. Default handler
 *    will be weak symbol and just dead loops. They can be
 *    overwritten by other handlers */
    .macro	def_irq_handler	handler_name
    .weak	\handler_name
    .set	\handler_name, Default_Handler
    .endm

    def_irq_handler EXTI_IRQHandler       /* 0 */
    def_irq_handler IWDT_IRQHandler       /* 1 */
    def_irq_handler BLE_IRQHandler        /* 2 */
    def_irq_handler DMAC_IRQHandler       /* 3 */
    def_irq_handler BB_LP_IRQHandler      /* 4 */
    def_irq_handler BTMR_IRQHandler       /* 5 */
    def_irq_handler CTMR1_IRQHandler      /* 6 */
    def_irq_handler ADMR1_IRQHandler      /* 7 */
    def_irq_handler RTC_IRQHandler        /* 8 */
    def_irq_handler I2C1_IRQHandler       /* 9 */
    def_irq_handler SPIM_IRQHandler       /* 10*/
    def_irq_handler SPIS_IRQHandler       /* 11 */
    def_irq_handler UART1_IRQHandler      /* 12 */
    def_irq_handler UART2_IRQHandler      /* 13 */
    def_irq_handler AON_PMU_IRQHandler    /* 14 */
    def_irq_handler LVD33_IRQHandler      /* 15 */
    def_irq_handler BOD12_IRQHandler      /* 16 */
    def_irq_handler USB_IRQHandler        /* 17 */
    def_irq_handler USB_SOF_IRQHandler    /* 18 */
    def_irq_handler FSHC_IRQHandler       /* 19 */

    .end