double approx_exp(double power)
{
u8 i;
u32 int_part;
double frac_part;
double xn=1;
double result=0;
int_part=(u32)power;
frac_part=power -(double)int_part;
if(int_part>512) UsageFault_Handler();
//take taylor series x=0
for(i=0;i<EXP_ITERATION;i++)
{
result+=xn*_invfac_table[i];
xn=xn*frac_part;
}
//end take taylor series
//get from table
for(i=0;i<10;i++)
{
if(int_part&((u32)1<<i))
{
result*=_exp_square_table[i];
}
}
//end get from table
return result;
}
uint8 StackFloatPop(TSTACKFLOAT *s,float *value)
{
if(!StackFloatIsEmpty(s))
{
*value=s->value[s->top];
s->top--;
return 1;
}
UsageFault_Handler();//debug
return 0;
}
uint8 StackU8Pop(TSTACKU8 *s,uint8 *value)
{
if(!StackU8IsEmpty(s))
{
*value=s->value[s->top];
s->top--;
return 1;
}
UsageFault_Handler();//debug
return 0;
}
__attribute__((externally_visible)) void prvGetRegistersFromStack( uint32_t *pulFaultStackAddress )
{
/* These are volatile to try and prevent the compiler/linker optimising them
away as the variables never actually get used. If the debugger won't 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 register. */
volatile uint32_t pc; /* Program counter. */
volatile uint32_t psr;/* Program status register. */
r0 = pulFaultStackAddress[ 0 ];
r1 = pulFaultStackAddress[ 1 ];
r2 = pulFaultStackAddress[ 2 ];
r3 = pulFaultStackAddress[ 3 ];
r12 = pulFaultStackAddress[ 4 ];
lr = pulFaultStackAddress[ 5 ];
pc = pulFaultStackAddress[ 6 ];
psr = pulFaultStackAddress[ 7 ];
/* Silence "variable set but not used" error */
if (false) {
(void)r0; (void)r1; (void)r2; (void)r3; (void)r12; (void)lr; (void)pc; (void)psr;
}
if (SCB->CFSR & (1<<25) /* DIVBYZERO */) {
// stay consistent with the core and cause 5 flashes
UsageFault_Handler();
}
else {
PANIC(HardFault,"HardFault");
/* Go to infinite loop when Hard Fault exception occurs */
while (1)
{
}
}
}
