# ============================================
# Practice 5: 7-Segment Display
# Intelligent IoT Design & Experiments - Week 1
# ============================================
# Learning Objectives:
#   - Control multiple GPIO outputs
#   - Map data using dictionaries
#   - Understand the principle of 7-segment display
# ============================================
# 7-Segment Structure:
#      ── a ──
#     |       |
#     f       b
#     |       |
#      ── g ──
#     |       |
#     e       c
#     |       |
#      ── d ──   (dp)
# ============================================

from machine import Pin
import time

# --- Segment Pin Mapping (a~g, dp) ---
#   a=GPIO2, b=GPIO4, c=GPIO5, d=GPIO6,
#   e=GPIO7, f=GPIO8, g=GPIO9, dp=GPIO10
segment_pins = {
    'a':  Pin(2,  Pin.OUT),
    'b':  Pin(4,  Pin.OUT),
    'c':  Pin(5,  Pin.OUT),
    'd':  Pin(6,  Pin.OUT),
    'e':  Pin(7,  Pin.OUT),
    'f':  Pin(8,  Pin.OUT),
    'g':  Pin(9,  Pin.OUT),
    'dp': Pin(10, Pin.OUT),
}

# --- Number to Segment Mapping ---
# Order: (a, b, c, d, e, f, g)  1=ON, 0=OFF
DIGITS = {
    0: (1, 1, 1, 1, 1, 1, 0),
    1: (0, 1, 1, 0, 0, 0, 0),
    2: (1, 1, 0, 1, 1, 0, 1),
    3: (1, 1, 1, 1, 0, 0, 1),
    4: (0, 1, 1, 0, 0, 1, 1),
    5: (1, 0, 1, 1, 0, 1, 1),
    6: (1, 0, 1, 1, 1, 1, 1),
    7: (1, 1, 1, 0, 0, 0, 0),
    8: (1, 1, 1, 1, 1, 1, 1),
    9: (1, 1, 1, 1, 0, 1, 1),
}

# List of segment names (for order mapping)
SEG_ORDER = ['a', 'b', 'c', 'd', 'e', 'f', 'g']

def display_digit(num):
    """Display numbers 0-9 on 7-segment"""
    if num not in DIGITS:
        # Turn off everything if not a number
        for seg in segment_pins.values():
            seg.value(0)
        return
    
    pattern = DIGITS[num]
    for i, seg_name in enumerate(SEG_ORDER):
        segment_pins[seg_name].value(0 if pattern[i] else 1)
    
    print(f"Display: {num}")

def all_off():
    """Turn off all segments"""
    for seg in segment_pins.values():
        seg.value(0)

# --- Main: 0-9 Counter ---
print("=== Starting 7-Segment Display ===")
print("Displaying numbers 0 to 9 in sequence.")
print()

while True:
    for digit in range(10):
        display_digit(digit)
        time.sleep(1)
    
    # Blink effect before restarting
    for _ in range(3):
        all_off()
        time.sleep(0.2)
        display_digit(0)
        time.sleep(0.2)
    all_off()
    time.sleep(0.5)

# ============================================
# 💡 Practice Exercises:
#   1) Map alphabets A, b, C, d, E, F to display hexadecimal.
#   2) Create a clock effect using the decimal point (dp) as a blinking dot.
#   3) Implement a counter where buttons increase or decrease the number.
# ============================================