Microcomputer Systems 1

1. SulTan BINHUMOOD Final Project Presentation Microcomputer Systems 1

2. Project Info • My project idea is based on playing sound displaying different effects seen in everyday experiences.

3. EFFECTS • CHORUS chorus effect (sometimes chorusing effect) occurs when individual sounds are roughly the same and nearly (but never exactly) the same pitch converge and are perceived as one • ECHO A time-delayed electronic reflection of a speaker's voice.

4. Chorus - CODING • for(i = 0; i < BUFLEN; i++) • { • delay = (int)((1 - (cos(6.28 * 0.4 * input / 1000))) * 20); //eq'n for delay = D/2(1-(cos(2*pi*n*f)) • delay = input - delay; //usage of the delay in the output equation • if (delay < 0) • { • delay = 1000 + delay; //if the value of the delay go below 0, it retakes 5000 samples • } //it basically "goes back to the start" • buffer1[input] = (short) (pIn[i * 2]); • buffer2[input] = (short) (pIn[i * 2 + 1]); • x = (int)(buffer1[input] + 2 * buffer1[delay] / 3); //2/3 is alpha, which is like a volume control;it controls the intensity of the effect's signal • y = (int)(buffer2[input] + 2 * buffer1[delay] / 3); //x and y both have 16 bits stored in them • if(input >= 1000 - 1) //if the number of samples go beyond 5000, resets it to 0 • input = 0; • else • input++; • pOut[i * 2]= (x); • pOut[i * 2 + 1]= (y); // display output in the output buffer • } • }

5. Echo - CODING • void Echo_Effect(short *pIn, short *pOut) • { • inti; • short buffer1[1000]; • short buffer2[1000]; • static int input = 0; • int x, y=0; • for(i = 0; i < BUFLEN; i++) • { • buffer1[input] = (pIn[i * 2]) + (0.6 * buffer1[input]); • buffer2[input] = (pIn[i * 2 + 1]) + (0.6 * buffer2[input]); • x = (int) (buffer1[input]); • y = (int) (buffer2[input]); • if(input>= 1000-1) • input = 0; • else • input++; • pOut[i * 2] = (x); • pOut[i * 2 + 1] = (y); // display output in the output buffer • } • }

6. Run project • Run the actual project and show how the effects work. • > First select Passthrough to show the actual sound • > Next show Chorus Effect • > Show Echo Effect

7. The End • Any questions about the project or suggestions to improve the project?