EDIT: i fixed the problem, the guitar hookup wasnt seated all the way haha. Its always the little things. Thanks for the replies and suggestions!
I am modifying the following instructable https://www.instructables.com/Arduino-Guitar-Tuner/
but instead of having LEDs light up to show if the guitar is in tune or not, I am trying to make an LCD display the frequency. I'm having problems with troubleshooting, when I try different notes nothing is happening with the LCD so I turned on the serial monitor to see what values I was getting and it's just displaying 0 when I first turn the arduino on and then inf forever. Here is my code and there is also a circuit diagram and sample code in the instructable.
// Arduino Frequency Detection
//data storage variables
byte newData = 0;
byte prevData = 0;
unsigned int time = 0; //this keeps time and will send vals to store in timer
int timer[10]; //storage for timing
int slope[10]; //storage for slope
unsigned int totalTimer; //int for calculating period
unsigned int period; //storage for period of waveform
byte index = 0; //current storage index
float frequency; //storage for freq calcs
int maxSlope = 0; //calculate max slope
int newSlope = 0; //storage for current slope data
//match variables
byte noMatch = 0;
byte slopeTol = 3; //slope tolerance
int timerTol = 10; //timer tolerance
//amp detection variables
unsigned int ampTimer = 0;
byte maxAmp = 0;
byte checkMaxAmp;
byte ampThreshold = 10; //threshold for signal noise
//LCD display setup
#include <LiquidCrystal.h>
const int LCD_D7 = 2;
const int LCD_D6 = 3;
const int LCD_D5 = 4;
const int LCD_D4 = 5;
const int LCD_EN = 11;
const int LCD_RS = 13;
LiquidCrystal lcd(LCD_RS, LCD_EN, LCD_D4, LCD_D5, LCD_D6, LCD_D7);
const int LCD_WIDTH = 16;
const int LCD_HEIGHT = 2;
void setup() {
// put your setup code here, to run once:
Serial.begin(115200);
Serial.println("CLEARDATA");
Serial.println("LABEL,Frequency(Hz)");
// LCD
lcd.begin(LCD_WIDTH, LCD_HEIGHT);
lcd.print("Turning on...");
delay (2500);
lcd.clear();
cli();
// continuous sampling of analog pin 0 @ 38.5kHz
// clear ADCSRA and ADCSRB registers
ADCSRA = 0;
ADCSRB = 0;
ADMUX |= (1 << REFS0); //set reference voltage
ADMUX |= (1 << ADLAR); //left aligning the ADC value allows one to read the highest 8 bits from ADCH register only
ADCSRA |= (1 << ADPS2) | (1 << ADPS0); //set ADC clock with 32 prescaler-16mHz/32=50
ADCSRA |= (1 << ADATE); //enable auto trigger
ADCSRA |= (1 << ADIE); //enable interrupts when measurement complete
ADCSRA |= (1 << ADEN); //enable ADC
ADCSRA |= (1 << ADSC); //start ADC measurements
sei();
}
ISR(ADC_vect) {//when new ADC value ready
PORTB &= B11101111; //set pin 12 low (can change if using other pin)
prevData = newData; //store prev value
newData = ADCH; //get new value from A0
if (prevData < 127 && newData >= 127) { //if increasing and crossing midpoint
newSlope = newData - prevData; //calculate slope
if (abs(newSlope - maxSlope) < slopeTol) { //if slopes are equal record new data and reset time
slope [index] = newSlope;
timer[index] = time;
time = 0;
if (index == 0) { //new max slope just got reset
PORTB |= B00010000; //set pin 12 high
noMatch = 0;
index++; //increment index
}
else if (abs(timer[0] - timer[index]) < timerTol && abs(slope[0] - newSlope) < slopeTol) { //if timer duration and slopes match
//sum timer vals
totalTimer = 0;
for (byte i = 0; i < index; i++) {
totalTimer += timer[i];
}
period = totalTimer; //set period
timer[0] = timer[index];
slope[0] = slope[index];
index = 1;
PORTB |= B00010000; //set pin 12 high
noMatch = 0;
}
else { //crossing midpoint but not match
index++;
if (index > 9) {
reset();
}
}
}
else if (newSlope > maxSlope) {
maxSlope = newSlope;
time = 0;
noMatch = 0;
index = 0;
}
else {
noMatch++;
if (noMatch > 9) {
reset();
}
}
}
time++; //increment timer at rate of 38.5 kHz
ampTimer++; //increment amplitude timer
if (abs(127 - ADCH) > maxAmp) {
maxAmp = abs(127 - ADCH);
}
if (ampTimer == 1000) {
ampTimer = 0;
checkMaxAmp = maxAmp;
maxAmp = 0;
}
}
void reset() { //clean some variables
index = 0;
noMatch = 0;
maxSlope = 0;
}
// Determine correct freq and display
void frequencyCheck() {
// low E
if (frequency > 83.5 && frequency < 92) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" low E string too high.");
delay (2000);
lcd.clear();
}
if (frequency < 82) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" low E string too low.");
delay (2000);
lcd.clear();
}
if (frequency <= 83 && frequency >= 92) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" low E string in tune.");
delay (2000);
lcd.clear();
}
// A
if (frequency > 110.5 && frequency < 128) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" A string too high.");
delay (2000);
lcd.clear();
}
if (frequency < 109.5 && frequency > 93) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" A string too low.");
delay (2000);
lcd.clear();
}
if (frequency <= 110 && frequency >= 109) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" A string in tune.");
delay (2000);
lcd.clear();
}
// D
if (frequency > 147.5 && frequency < 170) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" D string too high.");
delay (2000);
lcd.clear();
}
if (frequency < 145 && frequency > 128.5) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" D string too low.");
delay (2000);
lcd.clear();
}
if (frequency <= 146 && frequency >= 147) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" D string in tune.");
delay (2000);
lcd.clear();
}
// G
if (frequency > 197 && frequency < 222) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" G string too high.");
delay (2000);
lcd.clear();
}
if (frequency < 196 && frequency > 171) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" G string too low.");
delay (2000);
lcd.clear();
}
if (frequency <= 197 && frequency >= 196) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" G string in tune.");
delay (2000);
lcd.clear();
}
// B
if (frequency > 248 && frequency < 288) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" B string too high.");
delay (2000);
lcd.clear();
}
if (frequency < 247 && frequency > 223) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" B string too low.");
delay (2000);
lcd.clear();
}
if (frequency <= 248 && frequency >= 247) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" B string in tune.");
delay (2000);
lcd.clear();
}
// high E
if (frequency > 331.5 && frequency < 400) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" high E string too high.");
delay (2000);
lcd.clear();
}
if (frequency < 329 && frequency > 289) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" high E string too low.");
delay (2000);
lcd.clear();
}
if (frequency <= 331 && frequency >= 330) {
lcd.print("Frequency=");
lcd.print(frequency);
lcd.print(" high E string in tune.");
delay (2000);
lcd.clear();
}
}
void loop() {
// put your main code here, to run repeatedly:
if (checkMaxAmp > ampThreshold) {
frequency = 38462 / float(period); //calc frequency timer rate/period
}
//stringCheck();
frequencyCheck();
Serial.println(frequency);
delay(100);
}
