#Question 1

from machine import Pin,I2C,Timer,ADC
from pico_i2c_lcd import I2cLcd
import utime
import random
#can only use 0,1 or 21,22 in hardware pi pico
sda=Pin(0)
scl=Pin(1)

i2c=I2C(0,sda=sda,scl=scl,freq=400000)

devices=i2c.scan()
i2caddr=devices[0]

pot=ADC(Pin(26))# set the poteniometer
lcd=I2cLcd(i2c,i2caddr,2,16)

while True:
    val=pot.read_u16()
    print(val)
    angle=90-(val/65535)*90 #65535 is the max value
    lcd.clear()
    lcd.putstr(str(angle))
    utime.sleep(1)

# Question 2
from machine import Pin,I2C,Timer,ADC
from pico_i2c_lcd import I2cLcd
import utime
import random
import time
import math
#can only use 0,1 or 21,22 in hardware pi pico
sda=Pin(0)
scl=Pin(1)

i2c=I2C(0,sda=sda,scl=scl,freq=400000)

devices=i2c.scan()
i2caddr=devices[0]

ntc=ADC(Pin(27))# set the 
lcd=I2cLcd(i2c,i2caddr,2,16)

def adc_to_temperature(adc_value):

    temp_celsius = 1 / (math.log((1 / (65536/adc_value)-1) / 3950 + (1 / 298.15))) - 273.15
    return temp_celsius

red_led=Pin(4,Pin.OUT)
green_led=Pin(2,Pin.OUT)
yellow_led=Pin(3,Pin.OUT)

temp_out_of_range_start = None

def fn(timer):
    global temp_out_of_range_start
    adc_value = ntc.read_u16()  
    temp_celsius = adc_to_temperature(adc_value)
    print(time.time())
    lcd.clear()
    lcd.putstr(str(temp_celsius))

    if 10 <= temp_celsius <= 33:
        green_led.on()
        yellow_led.off()
        red_led.off()
        temp_out_of_range_start = None
    
    else:
        yellow_led.on()
        green_led.off()
        red_led.off()
        
        # Start counting time outside the optimal range( for first time)
        if temp_out_of_range_start is None:
            temp_out_of_range_start = time.time()
        
        #when temp_out_of_range value is set(not None)
        elif time.time() - temp_out_of_range_start > 5:
            yellow_led.off()
            red_led.on()
            lcd.clear()
            lcd.putstr("DANGER!")
    utime.sleep(1)

timer=Timer(freq=1,mode=Timer.PERIODIC,callback=fn)