diff options
Diffstat (limited to 'lab5/RTDSP/intio.c')
| -rw-r--r-- | lab5/RTDSP/intio.c | 28 |
1 files changed, 10 insertions, 18 deletions
diff --git a/lab5/RTDSP/intio.c b/lab5/RTDSP/intio.c index e7ae084..a083765 100644 --- a/lab5/RTDSP/intio.c +++ b/lab5/RTDSP/intio.c @@ -46,8 +46,7 @@ #include "Matlab/coeff.txt" int N = sizeof(a)/sizeof(a[0]); -short* x; -double* y; +double* d; /******************************* Global declarations ********************************/ @@ -81,9 +80,8 @@ void init_HWI(void); void ISR_AIC(void); /********************************** Main routine ************************************/ void main(){ - x = (short*)calloc(N, sizeof(short)); - y = (double*)malloc(N * sizeof(double)); - memset(y, 0.0, N * sizeof(double)); + d = (double*)malloc(N * sizeof(double)); + memset(d, 0.0, N * sizeof(double)); // initialize board and the audio port init_hardware(); @@ -132,22 +130,16 @@ void init_HWI() /******************** INTERRUPT SERVICE ROUTINE ***********************/ void ISR_AIC() { - int i = N-1; - double Y = 0.0; + int i = 0; + short x_in = mono_read_16Bit(); + double y_out = d[0]; //Shift the values - for (; i > 0; --i) { - x[i] = x[i-1]; - y[i] = y[i-1]; - - Y += x[i] * b[i] - y[i] * a[i]; + for (; i < N-2; ++i) { + d[i] = d[i+1] + b[i] * x_in - a[i] * y_out; } - - x[0] = mono_read_16Bit(); - - Y += x[0] * b[0]; - y[0] = Y; + d[N-1] = b[N-1] * x_in - a[N-1] * y_out; - mono_write_16Bit((short)Y); + mono_write_16Bit((short)d[0]); } |