Mostrar en LCD 16x2 ángulo de TRIAC

Estoy implementando un drimmer con arduino UNO (módulo Bluetooth) y TRIAC. El caso es que quiero imprimir en la LCD el ángulo de disparo del TRIAC (0° a 180°) de acuerdo a la luminosidad del foco, sin embargo no me queda claro cómo modificar el código para hacer que se muestre en la pantalla dicho ángulo.

Código que tengo es:

#include <LiquidCrystal.h>

LiquidCrystal lcd(7, 8, 9, 10, 11 , 12);
int detectado = 0;
int valor=0;
int last_CH1_state = 0;

void setup() {
lcd.begin(16, 2);
lcd.setCursor(0,1);
Serial.begin(9600);

/*
* Port registers allow for lower-level and faster manipulation of the i/o pins of the microcontroller on an Arduino board.
* The chips used on the Arduino board (the ATmega8 and ATmega168) have three ports:
-B (digital pin 8 to 13)
-C (analog input pins)
-D (digital pins 0 to 7)
//All Arduino (Atmega) digital pins are inputs when you begin...
*/
PCICR |= (1 << PCIE0); //enable PCMSK0 scan
PCMSK0 |= (1 << PCINT0); //Set pin D8 trigger an interrupt on state change. Input from optocoupler
pinMode(3,OUTPUT); //Define D3 as output for the DIAC pulse
Serial.begin(9600); //Start serial com with the BT module (RX and TX pins)
}

void loop() {
//Read the value of the pot and map it from 10 to 10.000 us. AC frequency is 50Hz, so period is 20ms. We want to control the power
//of each half period, so the maximum is 10ms or 10.000us. In my case I've maped it up to 7.200us since 10.000 was too much
Serial.println(valor);
lcd.print(valor);
lcd.setCursor(0,1);
delay(100);
if(Serial.available()>0)
{
valor = map(Serial.read(),0,255,10000,10);
//In my case I've used valor = map(Serial.read(),0,255,7000,10); for better results
}
if (detectado)
{
delayMicroseconds(valor); //This delay controls the power
digitalWrite(3,HIGH);
delayMicroseconds(100);
digitalWrite(3,LOW);
detectado=0;
}
}

//This is the interruption routine
//----------------------------------------------

ISR(PCINT0_vect){
///////////////////////////////////// //Input from optocoupler
if(PINB & B00000001){ //We make an AND with the pin state register, We verify if pin 8 is HIGH???
if(last_CH1_state == 0){ //If the last state was 0, then we have a state change...
detectado=1; //We haev detected a state change!
}
}
else if(last_CH1_state == 1){ //If pin 8 is LOW and the last state was HIGH then we have a state change
detectado=1; //We haev detected a state change!
last_CH1_state = 0; //Store the current state into the last state for the next loop
}
}