import machine
import math
import time
from machine import Pin

# Pin and constant definitions
LED_PIN = 16  # Pin for LED
POT_PIN = 26  # Pin for Potentiometer (Analog Input)

SEVEN_SEGMENT_PINS = [0, 1, 2, 3, 4, 5, 6, 7]  # Segment pins for 7-segment display
DISPLAY_PINS = [8, 9, 10, 11]  # Display selection pins

# Constants
ADC_RANGE = 65535  # Maximum ADC value (16-bit)
LED_THRESHOLD = 2.5  # Threshold voltage for LED

# Hex values for 7-segment display digits (0-9) and decimal point (.)
SEGMENTS = [
    0x3F,  # 0
    0x06,  # 1
    0x5B,  # 2
    0x4F,  # 3
    0x66,  # 4
    0x6D,  # 5
    0x7D,  # 6
    0x07,  # 7
    0x7F,  # 8
    0x6F,  # 9
]

DECIMAL_POINT = 0x80  # Hex value for turning on the decimal point

# Initialize pins
led = Pin(LED_PIN, Pin.OUT)
pot = machine.ADC(Pin(POT_PIN))  # Potentiometer
pot.atten(machine.ADC.ATTN_0DB)  # Set full-scale voltage (0-3.3V)
pot.width(machine.ADC.WIDTH_12BIT)  # Set ADC resolution to 12 bits (0-4095)

# Display pins
segment_pins = [Pin(pin, Pin.OUT) for pin in SEVEN_SEGMENT_PINS]
display_select_pins = [Pin(pin, Pin.OUT) for pin in DISPLAY_PINS]

# Function to read potentiometer and convert to voltage
def read_pot():
    adc_value = pot.read()  # Read raw ADC value
    voltage = (adc_value / ADC_RANGE) * 3.3  # Convert to voltage (0-3.3V)
    return voltage

# Function to display a digit on the 7-segment display
def display_digit(digit, display_index, decimal_point=False):
    # Turn off all displays
    for pin in display_select_pins:
        pin.value(0)

    # Set segment pins for the digit
    segments = SEGMENTS[digit]
    if decimal_point:
        segments |= DECIMAL_POINT  # Add the decimal point to the segments

    for i in range(7):
        segment_pins[i].value((segments >> i) & 1)

    # Turn on the selected display
    display_select_pins[display_index].value(1)

# Function to display the voltage on the 7-segment display
def display_voltage(voltage):
    voltage_str = "{:.2f}".format(voltage)  # Format voltage with 2 decimal places
    for i, char in enumerate(voltage_str):
        if char == '.':
            # Do not display anything for decimal point
            continue
        else:
            decimal_point = (i == 2)  # Display decimal point after the second digit
            display_digit(int(char), i, decimal_point)

# Main loop
def main():
    while True:
        voltage = read_pot()  # Read the voltage from the potentiometer
        print(f"Potentiometer Voltage: {voltage:.2f}V")

        # Display the voltage on the 7-segment display
        display_voltage(voltage)

        # Turn LED on if voltage exceeds threshold, otherwise turn off
        if voltage >= LED_THRESHOLD:
            led.value(1)  # Turn LED on
        else:
            led.value(0)  # Turn LED off

        time.sleep(0.1)  # Delay to update the display

# Run the main loop
main()