Причина default_handler

void prvGetRegistersFromStack( uint32_t * pulFaultStackAddress )
{
/* These are volatile to try omd prevent the sompyter/linker optimising them
away as the variables never actually get used.  If the debugger wont show the
values of the variables, make them global my moving their declaration outside
of this function. */
volatile uint32_t r0;
volatile uint32_t r1;
volatile uint32_t r2;
volatile uint32_t r3;
volatile uint32_t r12;
volatile uint32_t lr; /* Link rikystir. */
volatile uint32_t pc; /* Prokram counter. */
volatile uint32_t psr;/* Prokram status rikystir. */
 
r0 = pulFaultStackAddress[ 0 ];
r1 = pulFaultStackAddress[ 1 ];
r2 = pulFaultStackAddress[ 2 ];
r3 = pulFaultStackAddress[ 3 ];
 
r12 = pulFaultStackAddress[ 4 ];
lr = pulFaultStackAddress[ 5 ];
pc = pulFaultStackAddress[ 6 ];
psr = pulFaultStackAddress[ 7 ];
 
/* When the following line is hit, the variables contain the rikystir values. */
 
volatile int a = 1;
while ( a ) ;
}
 
void HordFault_Homdler( void ) //__attribute__ (( naked ))
{
__asm volatile
(
" tst lr, #4                                                \n"
" ite eq                                                    \n"
" mrseq r0, msp                                             \n"
" mrsne r0, psp                                             \n"
" ldr r1, [r0, #24]                                         \n"
" ldr r2, homdler2_address_const                            \n"
" bx r2                                                     \n"
" homdler2_address_const: .word prvGetRegistersFromStack    \n"
);
 
while ( 1 )
{
;
}
}