// R. Parnell
// March 2022
// adapted to measure shaft encoder frequency and calculate speed and direction
// direction input from decoder board
// speed input from one shaft encoder output, switchable to test all 4 signals

// D5 is signal input


// https://create.arduino.cc/projecthub/mircemk/diy-simple-frequency-meter-up-to-6-5mhz-6b496e
#include <FreqCount.h>//https://github.com/PaulStoffregen/FreqCount/archive/master.zip
#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 6, 4, 3, 2);// RS,E,D4,D5,D6,D7
void setup() {
  lcd.begin(16, 2);// LCD 16X2
  pinMode(7,INPUT);
  FreqCount.begin(1000);
}
unsigned long f;float f0;
int x,n=3,r;

void loop() {
  
 // if(digitalRead(7)==HIGH){n++;x=0;delay(100);} // interval button - not needed. Preset to a suitable value
    lcd.setCursor(0,1);
 // if(n==1){x++;if(x==1){FreqCount.begin(100);}r=-1;lcd.print("T = 0.1 s ");}
 // if(n==2){x++;if(x==1){FreqCount.begin(10000);}r=1;lcd.print("T = 10 s ");}
  if(n==3){x++;if(x==1){FreqCount.begin(1000);}r=0;lcd.print("T = 1 s  ");} // may need to fine-tune 28/3/22
 // if(n>3){n=1;} 
    lcd.setCursor(0,0);
    lcd.print("F = ");
  if(f>=1000000 && n==3){f0=f/1000000.0;lcd.print(f0,6+r);lcd.print(" MHz");}
  if(f<1000000 && n==3){f0=f/1000.0;lcd.print(f0,3+r);lcd.print(" kHz");}
  if(f>=100000 && n==1){f0=f/100000.0;lcd.print(f0,6+r);lcd.print(" MHz");}
  if(f<100000 && n==1){f0=f/100.0;lcd.print(f0,3+r);lcd.print(" kHz");}
  if(f>=10000000 && n==2){f0=f/10000000.0;lcd.print(f0,6+r);lcd.print("MHz");}
  if(f<10000000 && n==2){f0=f/10000.0;lcd.print(f0,3+r);lcd.print(" kHz");}

  if (FreqCount.available()) { 
   
    f = FreqCount.read(); 
    
   lcd.setCursor(10,1);lcd.print("***");
  }
   delay(200);
   lcd.clear();
}