import machine
import time
from machine import ADC
import utime

#Class Definition
class LCD():
    def __init__(self, addr=39, blen=1):
        sda = machine.Pin(0)
        scl = machine.Pin(1)
        self.bus = machine.I2C(0,sda=sda, scl=scl, freq=400000)
        #print(self.bus.scan())
        self.addr = addr
        self.blen = blen
        self.send_command(0x33) # Must initialize to 8-line mode at first
        time.sleep(0.005)
        self.send_command(0x32) # Then initialize to 4-line mode
        time.sleep(0.005)
        self.send_command(0x28) # 2 Lines & 5*7 dots
        time.sleep(0.005)
        self.send_command(0x0C) # Enable display without cursor
        time.sleep(0.005)
        self.send_command(0x01) # Clear Screen
        self.bus.writeto(self.addr, bytearray([0x08]))
    def write_word(self, data):
        temp = data
        if self.blen == 1:
            temp |= 0x08
        else:
            temp &= 0xF7
        self.bus.writeto(self.addr, bytearray([temp]))
    def send_command(self, cmd):
        # Send bit7-4 firstly
        buf = cmd & 0xF0
        buf |= 0x04               # RS = 0, RW = 0, EN = 1
        self.write_word(buf)
        time.sleep(0.002)
        buf &= 0xFB               # Make EN = 0
        self.write_word(buf)
        # Send bit3-0 secondly
        buf = (cmd & 0x0F) << 4
        buf |= 0x04               # RS = 0, RW = 0, EN = 1
        self.write_word(buf)
        time.sleep(0.002)
        buf &= 0xFB               # Make EN = 0
        self.write_word(buf)
    def send_data(self, data):
        # Send bit7-4 firstly
        buf = data & 0xF0
        buf |= 0x05               # RS = 1, RW = 0, EN = 1
        self.write_word(buf)
        time.sleep(0.002)
        buf &= 0xFB               # Make EN = 0
        self.write_word(buf)
        # Send bit3-0 secondly
        buf = (data & 0x0F) << 4
        buf |= 0x05               # RS = 1, RW = 0, EN = 1
        self.write_word(buf)
        time.sleep(0.002)
        buf &= 0xFB               # Make EN = 0
        self.write_word(buf)
    def clear(self):
        self.send_command(0x01) # Clear Screen
    def openlight(self):  # Enable the backlight
        self.bus.writeto(self.addr,bytearray([0x08]))
        # self.bus.close()
    def write(self, x, y, str):
        if x < 0:
            x = 0
        if x > 15:
            x = 15
        if y < 0:
            y = 0
        if y > 1:
            y = 1
        # Move cursor
        addr = 0x80 + 0x40 * y + x
        self.send_command(addr)
        for chr in str:
            self.send_data(ord(chr))
    def message(self, text):
        #print("message: %s"%text)
        for char in text:
            if char == '\n':
                self.send_command(0xC0) # next line
            else:
                self.send_data(ord(char))

#Main Program
CONVERSION_FACTOR = 3.3 / 65535
sensor = ADC(ADC.CORE_TEMP)
lcd = LCD()
while True:
    sensor_reading = sensor.read_u16()
    reading_scaled = sensor_reading * CONVERSION_FACTOR
    temperature = 27 - (reading_scaled - 0.706) / 0.001721
    #lcd.create_char(1,heart)
    string = str(temperature) + chr(223) + "F"
    lcd.message(string)
    utime.sleep(2)
    lcd.clear()