Steven Swenson
A program to automatically tune a guitar. Written by Justin Reidhead and Steven Swenson
Dependencies: FFT FrequencyFinder Motor NewTextLCD PinDetect mbed strings
Revision 12:03c189de6e2e, committed 2012-04-25
- Comitter:
- melangeaddict
- Date:
- Wed Apr 25 04:09:25 2012 +0000
- Parent:
- 11:bdad1acccdad
- Child:
- 13:948c7d19acb9
- Commit message:
- BOO YAAAAH slut;
Changed in this revision
| FrequencyFinder/FrequencyFinder.cpp | Show annotated file Show diff for this revision Revisions of this file |
| main.cpp | Show annotated file Show diff for this revision Revisions of this file |
--- a/FrequencyFinder/FrequencyFinder.cpp Wed Apr 25 00:42:46 2012 +0000
+++ b/FrequencyFinder/FrequencyFinder.cpp Wed Apr 25 04:09:25 2012 +0000
@@ -46,13 +46,13 @@
if (j<200)//~48Hz
signal_array[j]=0;
else if (j<400)//~97Hz
- signal_array[j]=signal_array[j]*5;
+ signal_array[j]=signal_array[j]*3;
else if (j<600)//~146Hz
signal_array[j]=signal_array[j]*6;
else if (j<900)//~219Hz
- signal_array[j]=signal_array[j]*7;
+ signal_array[j]=signal_array[j]*10;
else if (j<1200)//292Hz
- signal_array[j]=signal_array[j]*25;
+ signal_array[j]=signal_array[j]*12;
else
signal_array[j]=signal_array[j]*30;
}
--- a/main.cpp Wed Apr 25 00:42:46 2012 +0000
+++ b/main.cpp Wed Apr 25 04:09:25 2012 +0000
@@ -66,6 +66,7 @@
bool check_threshold(float);//check to make sure the frequency is valid (frequency to check)
void LED_initialize();//Initialization sequence for LEDs, called at start-up
void set_LED(int led, int value);//sets or clears an LED: Blue=1(in tune), Red=2(flat), Green=3(sharp). Value=1(off), 0(on);
+int get_steps(float desired, float current);
//*************************************************
//*********************main************************
int main() {
@@ -79,9 +80,9 @@
int state=0,next_state=0;
- //int num_steps=0;
+ int num_steps=0;
//float old_freq=0;
- //int found_frequency=0;
+ short current_direction=up;
float new_freq=0;
float desired_freq=0;
strings *temp=&strings_array[0];
@@ -109,6 +110,7 @@
break;
//-----------------------------------------
case 2://begin the actual tuning
+
temp=&strings_array[selected_string];
desired_freq=temp->get_freq();//Get the desired frequency for the string selected
//old_freq=desired_freq;//We have to initalize it to something...
@@ -119,34 +121,40 @@
case 3://Do the dirty work of tuning
new_freq=guitar.find_frequency();//Get the current frequency of the string
- //if (new_freq>(desired_freq+50) || new_freq<(desired_freq-50)) {//If the new frequency is wildly out of whack
- //new_freq=guitar.find_frequency();//Get the current frequency of the string, again
- // break;
- //}
- //num_steps=-5*abs(new_freq-old_freq);
- // old_freq=new_freq;
+ if (desired_freq*2.2>new_freq && desired_freq*1.8<new_freq) {
+ new_freq=new_freq/2;
+ }
if (check_threshold(new_freq)) {//The check_threshold function makes sure the frequency is valid (less than 500 Hz)
+
+ num_steps=get_steps(desired_freq, new_freq);
+
if ((desired_freq-.5)<new_freq && (desired_freq+.5)>new_freq) {//We are within .5Hz of the desired frequency
- //if (found_frequency==0) {
- // found_frequency++;
- // next_state=3;
- // break;
- //}
+ new_freq=guitar.find_frequency();
+ if ((desired_freq-.5)>new_freq || (desired_freq+.5)<new_freq) {//This checks the frequency again to make sure we are close
+ next_state=3;
+ break;
+ }
+
lcd.cls();
lcd.printf("String %d\ntuned",selected_string+1);
set_LED(1,0);//blue on
set_LED(2,1);//red off;
set_LED(3,1);//green off
- wait(.5);
+ wait(1);
start_tuning=false;
output_menu();
setup_buttons();
next_state=0;
} else if ((desired_freq-.5)>new_freq) {//We are too low, and need to turn the string tigher
+ if (current_direction==down) {
+ num_steps+=18;//For deadband
+ current_direction=up;
+ }
+
lcd.cls();
lcd.printf("Tuning up");
@@ -156,12 +164,17 @@
//found_frequency=0;
- wait(.5);
+ //wait(.5);
- motor.motor_turn(up,10);//TODO:Adjust # of steps
+ motor.motor_turn(up,num_steps);//TODO:Adjust # of steps
next_state=3;
} else {//We are too high, and need to loosen the string
+ if (current_direction==up) {
+ num_steps+=18;//For deadband
+ current_direction=down;
+ }
+
lcd.cls();
lcd.printf("Tuning down");
set_LED(1,1);//blue off
@@ -170,9 +183,9 @@
//found_frequency=0;
- wait(.5);
+ //wait(.5);
- motor.motor_turn(down,10);
+ motor.motor_turn(down,num_steps);
next_state=3;
}
} else {
@@ -224,19 +237,19 @@
}
if (start_tuning) {
- lcd.cls();
-
- lcd.locate(9,0);
- lcd.printf("%f",new_freq);
- lcd.locate(9,1);
- lcd.printf("%f",desired_freq);
+ if (check_threshold(new_freq)) {
+ lcd.cls();
+ lcd.locate(9,0);
+ lcd.printf("%f",new_freq);
+ lcd.locate(9,1);
+ lcd.printf("%f",desired_freq);
- lcd.locate(0,1);
- lcd.printf("Desired");
- lcd.locate(0,0);
- lcd.printf("Detected");
+ lcd.locate(0,1);
+ lcd.printf("Desired");
+ lcd.locate(0,0);
+ lcd.printf("Detected");
+ }
}
-
}//end while
// return 0;
@@ -254,7 +267,7 @@
lcd.printf("Select Pitch: ");
lcd.printf("%s",temp->get_note());
//wait(.5);
-
+
set_LED(1,0);//Turn blue LED on
set_LED(2,1);
set_LED(3,1);
@@ -466,19 +479,49 @@
bool check_threshold(float freq) {
strings *temp=&strings_array[selected_string];
float desired_freq=temp->get_freq();//Get the desired frequency for the string selected
-
- if (freq>(desired_freq+75) || freq<(desired_freq-75) || freq>500) {//new_freq>(desired_freq+50) || new_freq<(desired_freq-50)
+
+ int hertz=0;
+ switch (selected_string) {
+ case 0:
+ hertz=85;
+ break;
+
+ case 1:
+ hertz=66;
+ break;
+
+ case 2:
+ hertz=53;
+ break;
+
+ case 3:
+ hertz=42;
+ break;
+
+ case 4:
+ hertz=29;
+ break;
+
+ case 5:
+ hertz=22;
+ break;
+
+ default:
+ break;
+ }
+
+ if (freq>(desired_freq+hertz) || freq<(desired_freq-hertz) || freq>500) {//new_freq>(desired_freq+50) || new_freq<(desired_freq-50)
lcd.cls();
lcd.printf("Pluck string %d\nagain",selected_string+1);
-
+
set_LED(1,1);
set_LED(2,1);
set_LED(3,1);//Turn led off
-
+
set_LED(2,0);
set_LED(3,0);//Make the LED turn yellow
-
- wait(.5);
+
+ //wait(.5);
return false;
} else
return true;
@@ -566,4 +609,78 @@
return;
+}
+//***********************************
+//********get_steps*****************
+int get_steps(float desired, float current) {
+
+ float difference=abs(desired-current);
+
+ switch (selected_string) {
+ case 5:
+ if (difference>10) {
+ return 60;
+ } else if (difference>3) {
+ return 35;
+ } else if (difference>1) {
+ return 15;
+ } else {
+ return 10;
+ }
+ case 4:
+ if (difference>10) {
+ return 60;
+ } else if (difference>3) {
+ return 40;
+ } else if (difference>1) {
+ return 23;
+ } else {
+ return 10;
+ }
+ case 3:
+ if (difference>10) {
+ return 40;
+ } else if (difference>3) {
+ return 25;
+ } else if (difference>1) {
+ return 15;
+ } else {
+ return 10;
+ }
+ case 2:
+ if (difference>10) {
+ return 33;
+ } else if (difference>3) {
+ return 20;
+ } else if (difference>1) {
+ return 15;
+ } else {
+ return 10;
+ }
+ case 1:
+ if (difference>10) {
+ return 30;
+ } else if (difference>3) {
+ return 20;
+ } else if (difference>1) {
+ return 10;
+ } else {
+ return 7;
+ }
+ case 0:
+ if (difference>10) {
+ return 20;
+ } else if (difference>3) {
+ return 15;
+ } else if (difference>1) {
+ return 8;
+ } else {
+ return 4;
+ }
+
+
+ default:
+ return 0;
+ break;
+ }//end switch
}
\ No newline at end of file