.syntax unified
.cpu cortex-m4

.section .text
.global _init
_init:
    ldr r0, =0x1003E000
    mov sp, r0

    ldr r0, =_vector_table
    ldr r1, =0xE000ED08
    str r0, [r1]

    push.w {r2-r9,r11,lr}
    bl main
    pop.w {r2-r9,r11,lr}
1:  b 1b

.section .vectors
_vector_table:
    .word _stack_top
    .word _init
    .word NMI_Handler
    .word HardFault_Handler
    .word MemManage_Handler
    .word BusFault_Handler
    .word UsageFault_Handler
    .word 0                    /* Reserved */
    .word 0                    /* Reserved */
    .word 0                    /* Reserved */
    .word 0                    /* Reserved */
    .word SVC_Handler
    .word DebugMon_Handler
    .word 0                    /* Reserved */
    .word PendSV_Handler
    .word SysTick_Handler

/* default */
.weak NMI_Handler
.weak HardFault_Handler
.weak MemManage_Handler
.weak BusFault_Handler
.weak UsageFault_Handler
.weak SVC_Handler
.weak DebugMon_Handler
.weak PendSV_Handler
.weak SysTick_Handler

.thumb_set NMI_Handler, Default_Handler
.thumb_set HardFault_Handler, Default_Handler
.thumb_set MemManage_Handler, Default_Handler
.thumb_set BusFault_Handler, Default_Handler
.thumb_set UsageFault_Handler, Default_Handler
.thumb_set SVC_Handler, Default_Handler
.thumb_set DebugMon_Handler, Default_Handler
.thumb_set PendSV_Handler, Default_Handler
.thumb_set SysTick_Handler, Default_Handler

Default_Handler:
    b Default_Handler