Digital Signal Processing Reference
In-Depth Information
for (i=0; i<N; i++)
{
dly[i] = 0;
//init buffer
h[1][i] = hlp[i];
//start addr of lowpass1500
coeff
h[2][i] = hhp[i];
//start addr of highpass1500
coeff
h[3][i] = hbp[i];
//start addr of bandpass1500
coeff
h[4][i] = hbs[i];
//start addr of bandstop1500
coeff
}
comm_intr();
//init DSK, codec, McBSP
while(1);
//infinite loop
}
In addition to the main FIR filter implementation program,
Fir4types.c,
given above, we also require a
gel
or
slider file,
which will enable us to step
through the four different kinds of filters when applied to the input voice
or music signal. The
FIR4types.gel
file is given below.
/*FIR4types.gel Gel file for 4 different filters:
LP,HP,BP,BS*/
menuitem “Filter Characteristics”
slider Filter(1,4,1,1,filterparameter)//*from 1 to 4,incr
by 1*/
{
FIR_number = filterparameter; //*for 4 FIR filters*/
}
Step 3: Setting up the 6711 DSK for filter implementation
The procedures for this step are identical to the ones given in the previous
two experiments, described in Section 8.2 and Section 8.3.
•
Creating a new project file
•
In CCS, select
Project
and then
New
. A window named
Project
Creation
will appear.
•
In the field labeled
Project Name
, enter
filtering_audio
. In the
field 'Location', click on the on the right side of the field and
browse to the folder
c:\ti\myprojects\filtering_audio\
.
