MrAntex · December 21, 2022 22:40 · Dec 21, 2022
diff --git a/audio_lab_software.c b/audio_lab_software.c
@@ -0,0 +1,124 @@
+
+// Filtering function using 2 for loops instead of one with a modulo because it turned out to be way more efficient
+// indexVal is the position of the current sample, it decreases each loop but staying in [0;currentSize]
+void filter(){
+
+	for(int w = indexVal ; w < currentSize ; w++){
+		toReturn[0] += currentCoeffs[w-indexVal] * bufferL[w];
+		toReturn[1] += currentCoeffs[w-indexVal] * bufferR[w];
+	}
+
+	for(int l = 0 ; l < indexVal ; l++){
+		toReturn[0] += currentCoeffs[currentSize-indexVal+l] * bufferL[l];
+		toReturn[1] += currentCoeffs[currentSize-indexVal+l] * bufferR[l];
+	}
+
+
+}
+
+// Changing the used filter by changing the used coefficients and the number of them (currentSize)
+void applyFilter(int filter){
+	switch(filter){
+	case 0: // Basic HP
+		currentCoeffs = HP;
+		currentSize = N_HP;
+		break;
+
+	case 1: // Basic LP
+		currentCoeffs = LP;
+		currentSize = N_LP;
+		break;
+
+	case 2: // None
+		currentCoeffs = None;
+		currentSize = N_None;
+		break;
+
+	case 3: // LP 2
+		currentCoeffs = LP2;
+		currentSize = N_LP2;
+		break;
+
+	case 99:
+		currentCoeffs = F99;
+		currentSize = N_F99;
+		break;
+	}
+
+	indexVal = currentSize-1;
+}
+
+
+
+
+int main()
+{
+
+	init_platform();
+
+	print("Started!\n\r");
+
+	AudioInitialize(SCU_TIMER_ID, AUDIO_IIC_ID, AUDIO_CTRL_BASEADDR);
+
+	initialize_FIFO(AUDIO_FIFO);
+	initialize_FIFO(FIR_FIFO);
+
+	applyFilter(99);
+
+
+
+	int SampleL, SampleR;
+
+
+	int j=0;
+	int time_now=0;
+	int time_func = 0;
+	int t = 0;
+
+	int tim_now_filter = 0;
+
+	int currentFilter = 0;
+
+	int indexVal = currentSize-1;
+
+
+
+	while (1){
+
+		if(j%2==0){ // Every 2 loops
+			t = Xil_In32(GLOBAL_TMR_BASEADDR + GTIMER_COUNTER_LOWER_OFFSET) - time_now;
+		}
+
+		int newSample[] = {(int) I2SFifoRead(AUDIO_FIFO), (int) I2SFifoRead(AUDIO_FIFO)};
+
+		bufferL[indexVal] = newSample[0];
+		bufferR[indexVal] = newSample[1];
+
+		toReturn[0] = 0;
+		toReturn[1] = 0;
+
+		time_now = Xil_In32(GLOBAL_TMR_BASEADDR + GTIMER_COUNTER_LOWER_OFFSET);
+
+		filter();
+
+		time_func = Xil_In32(GLOBAL_TMR_BASEADDR + GTIMER_COUNTER_LOWER_OFFSET) - time_now;
+
+
+		if(j%100000 == 0){ // Every 2-3 seconds
+			xil_printf("Filter : %d, Loop : %d\n",time_func, t);
+			j = 0;
+		}
+
+
+		I2SFifoWrite(AUDIO_FIFO, toReturn[0]);
+		I2SFifoWrite(AUDIO_FIFO, toReturn[1]);
+
+		j++;
+
+    // Updating indexVal
+		indexVal = indexVal == 0 ? currentSize-1 : (indexVal-1)%currentSize;
+	}
+
+	cleanup_platform();
+	return 0;
+}