Robin2:
AbdulW87:
the problem with your suggestion is that the servos move a pan and tilt mount and i require one reading per angle.
I don't understand ( a) what you mean about 1 reading per angle or ( b) how my code excludes anything you want.
My code was only intended as a very generalized suggestion.
...R
sorry i should have been clear and maybe i didnt get what you were trying to say.
By 1 reading per angle i mean, the pan and tilt mount will move in a similar fashion as scan lines in a TV go, from left to right (or right to left) from the top to the bottom of the screen. Now break the horizontal line into say 9 angles of 10 degree each, so for the first line i get 9 reading then move to next line vertically and repeat the process. around 5 lines vertically that makes a total of 45 readings. I think it would be appropriate to say like a grid.
with the tone() command i was able to produce a sound frequency for all the 45 combination of angles but was limited to low frequencies. The mic responds better ot frequencies between the range of 4kHz and 12kHz, which i am not sure can be produced by the tone function in a sinusoidal waveform thus the decision to choose interrupts.
Which brings me to my recent problem, i copied a piece of code and ran it on arduino. the code was supposed to produce sample rate of 40kHz but the oscilloscope read 400Hz (100 times less), i tried tinkering with the prescalar, and the timer modes but nothing works. the code was taken from this instructable http://www.instructables.com/id/Arduino-Audio-Output/?ALLSTEPS
//Sine out w/ 40kHz sampling rate
//by Amanda Ghassaei
//http://www.instructables.com/id/Arduino-Audio-Output/
//Sept 2012
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
*/
byte sine[] = {127, 134, 142, 150, 158, 166, 173, 181, 188, 195, 201, 207, 213, 219, 224, 229, 234, 238, 241, 245, 247, 250, 251, 252, 253, 254, 253, 252, 251, 250, 247, 245, 241, 238, 234, 229, 224, 219, 213, 207, 201, 195, 188, 181, 173, 166, 158, 150, 142, 134, 127, 119, 111, 103, 95, 87, 80, 72, 65, 58, 52, 46, 40, 34, 29, 24, 19, 15, 12, 8, 6, 3, 2, 1, 0, 0, 0, 1, 2, 3, 6, 8, 12, 15, 19, 24, 29, 34, 40, 46, 52, 58, 65, 72, 80, 87, 95, 103, 111, 119,};
int t = 0;//time
void setup(){
//set digital pins 0-7 as outputs
for (int i=0;i<8;i++){
pinMode(i,OUTPUT);
}
cli();//disable interrupts
//set timer0 interrupt at 40kHz
TCCR0A = 0;// set entire TCCR0A register to 0
TCCR0B = 0;// same for TCCR0B
TCNT0 = 0;//initialize counter value to 0
// set compare match register for 40khz increments
OCR0A = 49;// = (16*10^6) / (40000*8) - 1 (must be <256)
// turn on CTC mode
TCCR0A |= (1 << WGM01);
// Set CS11 bit for 8 prescaler
TCCR0B |= (1 << CS11);
// enable timer compare interrupt
TIMSK0 |= (1 << OCIE0A);
sei();//enable interrupts
}
ISR(TIMER0_COMPA_vect){ //40kHz interrupt routine
PORTD = sine[t];//send sine wave to DAC, centered around (127/255)*5 = 2.5V
t++;//increment t
if (t > 99){//reset t to zero
t = 0;
}
}
void loop(){
//do other stuff here
}