interrupt void Codec_ISR()
///////////////////////////////////////////////////////////////////////
// Purpose: Codec interface interrupt service routine
//
// Input: None
//
// Returns: Nothing
//
// Calls: CheckForOverrun, ReadCodecData, WriteCodecData
//
// Notes: None
///////////////////////////////////////////////////////////////////////
{
/* add any local variables here */
static Uint8 fill_index = INITIAL_FILL_INDEX; // index of buffer to fill
static Uint8 dump_index = INITIAL_DUMP_INDEX; // index of buffer to dump
static Uint32 sample_count = 0; // current sample count in buffer
if(CheckForOverrun()) // overrun error occurred (i.e. halted DSP)
return; // so serial port is reset to recover
CodecDataIn.UINT = ReadCodecData(); // get input data samples
/* add your code starting here */
// store input in buffer
buffer[fill_index][ LEFT][sample_count] = CodecDataIn.Channel[ LEFT];
buffer[fill_index][RIGHT][sample_count] = CodecDataIn.Channel[RIGHT];
// bound output data before packing
// use saturation of SPINT to limit to 16-bits
CodecDataOut.Channel[ LEFT] = _spint(buffer[dump_index][ LEFT][sample_count] * 65536) >> 16;
CodecDataOut.Channel[RIGHT] = _spint(buffer[dump_index][RIGHT][sample_count] * 65536) >> 16;
// pack output data without bounding
// CodecDataOut.channel[ LEFT] = buffer[dump_index][LEFT][sample_count];
// CodecDataOut.channel[RIGHT] = buffer[dump_index][RIGHT][sample_count];
// update sample count and swap buffers when filled
if(++sample_count >= BUFFER_LENGTH) {
sample_count = 0;
ready_index = fill_index;
if(++fill_index >= NUM_BUFFERS)
fill_index = 0;
if(++dump_index >= NUM_BUFFERS)
dump_index = 0;
if(buffer_ready == 1) // set a flag if buffer isn't processed in time
over_run = 1;
buffer_ready = 1;
}
/* end your code here */
WriteCodecData(CodecDataOut.UINT); // send output data to port
}
interrupt void Codec_ISR()
///////////////////////////////////////////////////////////////////////
// Purpose: Codec interface interrupt service routine
//
// Input: None
//
// Returns: Nothing
//
// Calls: CheckForOverrun, ReadCodecData, WriteCodecData
//
// Notes: None
///////////////////////////////////////////////////////////////////////
{
/* add any local variables here */
float output; //, *p;
int indLeft, indRight;
if(CheckForOverrun()) // overrun error occurred (i.e. halted DSP)
return; // so serial port is reset to recover
CodecDataIn.UINT = ReadCodecData(); // get input data samples
/* I added my mono FIR filter routine here */
xLeft[sampleInd] = CodecDataIn.Channel[LEFT];
output = 0; // set up for LEFT channel
indLeft = sampleInd;
indRight = sampleInd + 1;
if(++sampleInd > N)
sampleInd = 0;
if(indRight > N)
indRight = 0;
for (i = 0; i < (N+1)/2; i++) { // do LEFT channel FIR
output += ( ( xLeft[indLeft--] * B[i] ) + ( xLeft[indRight++] * B[i] ) );
if(indLeft < 0)
indLeft = N;
if(indRight > N)
indRight = 0;
}
if( ( N % 2 ) == 0 )
{
output += ( xLeft[ indLeft-- ] * B[ ( N/2 )] );
}
CodecDataOut.Channel[LEFT] = output; // store filtered value
CodecDataOut.Channel[RIGHT] = output; // store filtered value
/* end of my mono FIR filter routine */
WriteCodecData(CodecDataOut.UINT); // send output data to port
}
interrupt void Codec_ISR()
///////////////////////////////////////////////////////////////////////
// Purpose: Codec interface interrupt service routine
//
// Input: None
//
// Returns: Nothing
//
// Calls: CheckForOverrun, ReadCodecData, WriteCodecData
//
// Notes: None
///////////////////////////////////////////////////////////////////////
{
/* add any local variables here */
int sTemp;
float left = 0.0f;
float right = 0.0f;
float out = 0.0f;
float currentIn = 0.0f;
if(CheckForOverrun()) // overrun error occurred (i.e. halted DSP)
return; // so serial port is reset to recover
CodecDataIn.UINT = ReadCodecData(); // get input data samples
currentIn = CodecDataIn.Channel[LEFT];
delayed[0] = currentIn;
left = delayed[0];
for(i = 1; i < N; i++)
{
left -= (A[i] * delayed[i]);
}
delayed[0] = left;
for(i = 0; i < N; i++)
{
right += ( B[i] * delayed[i] );
}
for(i = N; i > 0; i--)
delayed[i] = delayed[i-1];
CodecDataOut.Channel[LEFT] = right;
WriteCodecData(CodecDataOut.UINT); // send output data to port
return;
}
interrupt void Codec_ISR()
///////////////////////////////////////////////////////////////////////
// Purpose: Codec interface interrupt service routine
//
// Input: None
//
// Returns: Nothing
//
// Calls: CheckForOverrun, ReadCodecData, WriteCodecData
//
// Notes: None
///////////////////////////////////////////////////////////////////////
{
/* add any local variables here */
float xLeft, xRight, yLeft, yRight;
if(CheckForOverrun()) // overrun error occurred (i.e. halted DSP)
return; // so serial port is reset to recover
CodecDataIn.UINT = ReadCodecData(); // get input data samples
/* add your code starting here */
// this example simply copies sample data from in to out
xLeft = CodecDataIn.Channel[ LEFT];
xRight = CodecDataIn.Channel[ RIGHT];
yLeft = xLeft;
yRight = xRight;
CodecDataOut.Channel[ LEFT] = yLeft;
CodecDataOut.Channel[RIGHT] = yRight;
/* end your code here */
WriteCodecData(CodecDataOut.UINT); // send output data to port
}
interrupt void Codec_ISR()
///////////////////////////////////////////////////////////////////////
// Purpose: Codec interface interrupt service routine
//
// Input: None
//
// Returns: Nothing
//
// Calls: CheckForOverrun, ReadCodecData, WriteCodecData
//
// Notes: None
///////////////////////////////////////////////////////////////////////
{
/* add any local variables here */
Int32 symbol;
Int32 i;
if(CheckForOverrun()) // overrun error occurred (i.e. halted DSP)
return; // so serial port is reset to recover
CodecDataIn.UINT = ReadCodecData(); // get input data samples
/* add your code starting here */
// I added my impulse modulated, QPSK routine here
if (counter == 0) {
symbol = rand() & 3; /* generate 2 random bits */
xI[0] = QPSK_LUT[symbol][RIGHT]; // lookup the I symbol
xQ[0] = QPSK_LUT[symbol][ LEFT]; // lookup the Q symbol
}
output = 0;
switch(counter & 3) {
case 0: // perform the I impulse modulation based on the FIR filter, B[N]
for (i = 0; i < 6; i++) {
output += xI[i]*B[counter + 20*i]; // perform the "I" dot-product
}
break;
case 1: // perform the Q impulse modulation based on the FIR filter, B[N]
for (i = 0; i < 6; i++) {
output -= xQ[i]*B[counter + 20*i]; // perform the "Q" dot-product
}
break;
case 2: // perform the -I impulse modulation based on the FIR filter, B[N]
for (i = 0; i < 6; i++) {
output -= xI[i]*B[counter + 20*i]; // perform the "-I" dot-product
}
break;
default: // perform the -Q impulse modulation based on the FIR filter, B[N]
for (i = 0; i < 6; i++) {
output += xQ[i]*B[counter + 20*i]; // perform the "-Q" dot-product
}
break;
}
if (counter == (samplesPerSymbol - 2)) {
/* shift xI[] in preparation to receive the next I input */
for (i = 5; i > 0; i--) {
xI[i] = xI[i-1]; // setup xI[] for the next input value
}
}
else if (counter >= (samplesPerSymbol - 1)) {
counter = -1; // reset in preparation for the next set of bits
/* shift xQ[] in preparation to receive the next Q input */
for (i = 5; i > 0; i--) {
xQ[i] = xQ[i-1]; // setup xQ[] for the next input value
}
}
counter++;
CodecDataOut.Channel[LEFT] = output_gain*output; // setup the LEFT output value
CodecDataOut.Channel[RIGHT] = CodecDataOut.Channel[LEFT]; // copy to RIGHT
// end of my impulse modulated, QPSK routine here
/* end your code here */
WriteCodecData(CodecDataOut.UINT); // send output data to port
}