from machine import ADC
import math
import utime

from machine import SoftI2C, Pin
from ssd1306 import SSD1306_I2C

# Setup OLED
i2c = SoftI2C(scl=Pin(3), sda=Pin(2))
oled = SSD1306_I2C(128, 64, i2c)


# NTC constant parameters
ntc_resistance = 10000 # NTC resistance value（Unit: ohms）
ntc_beta = 3950 # NTC Beta coefficency

# Initilize ADC
adc = ADC(28)  #set GPIO 28 as the ADC input channel for NTC output

# Read NTC sensor ADC and calculate temperature
def read_temperature():
    # Read ADC
    adc_value = adc.read_u16()
    adc_value = adc_value & 0xFFF
    #print(adc_value)

    # Calculate resistance
    resistance = (4095 / adc_value) * 3300 - 3300

    # Calculate temperature with Steinhart-Hart formula
    steinhart = resistance / ntc_resistance
    steinhart = math.log(steinhart)
    steinhart /= ntc_beta
    steinhart += 1.0 / (25 + 273.15)
    steinhart = 1.0 / steinhart
    temperature = steinhart - 273.15
    return temperature

# Main Function
# Startup display
oled.text("JX College",25,30)
oled.show()
utime.sleep(2)
oled.fill(0)

while True:
    temp = read_temperature()
    print("Temperature: {} degrees Celsius".format(temp))
    oled.text("Real Temperature:",0,25)
    oled.text(str('%.2f C'%(temp)),35,35)
    
    # OLED start show
    oled.show()
    utime.sleep(1)
    oled.fill(0)