int16 iir_filter(int16 tmp)
{
int i;
x[0] = (double) (tmp); // Read received sample and perform typecast
y2[0] = 0; // Initialize output
for(i = 0;i <= FILTER_LENGTH;i++) // Run FIR filter for each received sample
{
y2[0] += b2[i]*x[i];
}
for(i = 1;i <= FILTER_LENGTH;i++) // Run FIR filter for each received sample
{
y2[0] -= a2[i]*y2[i];
}
for(i = FILTER_LENGTH-1;i >= 0;i--) // Roll x array in order to hold old sample inputs
{
x[i+1] = x[i];
y2[i+1] = y2[i];
}
return floor_and_convert(y2[0]);
}
int low_pass_filter(int data)
{
int i;
x_low[0] = (double) data;
y_low[0] = 0;
for(i = 0;i <= FILTER_LENGTH_low;i++) // Run IIR filter for each received sample
{
y_low[0] += b_low[i]*x_low[i];
}
for(i =1;i <= FILTER_LENGTH_low;i++) // Roll x array in order to hold old sample inputs
{
y_low[0] -= a_low[i]*y_low[i];
}
for(i = FILTER_LENGTH_low-1;i >= 0;i--)
{
x_low[i+1]=x_low[i];
y_low[i+1]=y_low[i];
}
return floor_and_convert(y_low[0]);
}
int16 filter(int16 data_in)
{
x[0] = (float) data_in;
y = 0;
for(i = 0;i <= FILTER_LENGTH;i++)
{
y += b[i]*x[i];
}
for(i = FILTER_LENGTH-;i >= 0;i--)
{
x[i+] = x[i];
}
return floor_and_convert(y);
}
