User:Yoana Buzova/mrSTOCK

inspired by a small DC motor(ripped off a scanner) with an optoelectronic sensor and a transparent wheel with black stripes to determine it's speed and direction.

Then ----> Andre's suggestion to check Derek Holzer's tonewheels .... his research in crossings in history between mathematics, physics, electronics and communications theory which found realization in the industries of motion picture films, music, surveillance technology and finally digital communications.

some names+tags

Lev Theremin, Arseny Avraamov, (russian avant-gardea artitsts) --Boris Yankovsky, Evgeny Scholpo, Nikolai Voinov, Daphne Oram (oramics machine), Delia Derbyshire

optical sound in cinema ---- 'visual music' movement in cinema, Norman McLaren, Oscar Fischinger, Len Lye, Whitney brothers

workshop stuff

Stock showed me and Nan how to make an H bridge to control dc motor direction and speed control with pot

Dave showed how to transform light into sound here:

D class Amplifier

in order to understand how H bridge works ----->

and code.....

 /* "Class D Amplifier"
 using PWM and H-Bridge to drive a speaker
 */
 
 #include <avr/io.h>
 
 #define PWM9_ON  (_BV(COM1A1) | _BV(WGM10))
 #define PWM10_ON (_BV(COM1B1) | _BV(WGM10))
 #define PWM_OFF _BV(WGM10)
 
 void setup(void)
 {
   // configure Timer1 (pins 9 & 10) for Fast 8-bit PWM
   TCCR1A = PWM_OFF;
   TCCR1B = (_BV(WGM12) | _BV(CS10));
   
   digitalWrite(9, LOW);
   digitalWrite(10, LOW);
   pinMode(9, OUTPUT);
   pinMode(10, OUTPUT);
 }
 
 
 void set_pwm(int value)
 {
   if (value < 0)
   {
     if (value > -255)
     {
       OCR1BL = -value;
     } else {
       OCR1BL = 255;
     }
     TCCR1A = PWM10_ON;
   } 
   else if (value > 0)
   {
     if (value < 255)
     {
       OCR1AL = value;
     } else {
       OCR1AL = 255;
     }
     TCCR1A = PWM9_ON;
   } else {
     TCCR1A = PWM_OFF;
   }
 }
 
 
 void loop(void)
 {
   int input = analogRead(0) - 512;
   set_pwm(input*16);
   
 }