import machine
import time

# Define your keypad matrix (rows and columns) and corresponding GPIO pins
keypad_rows = [machine.Pin(13), machine.Pin(12), machine.Pin(11), machine.Pin(10)]
keypad_cols = [machine.Pin(9), machine.Pin(8), machine.Pin(7), machine.Pin(6)]

# Define the keypad layout (4x4)
keypad_layout = [
    ['1', '2', '3', 'A'],
    ['4', '5', '6', 'B'],
    ['7', '8', '9', 'C'],
    ['*', '0', '#', 'D']
]

# Initialize the keypad pins
for row in keypad_rows:
    row.init(machine.Pin.IN, pull=machine.Pin.PULL_UP)

for col in keypad_cols:
    col.init(machine.Pin.OUT)

# Function to scan the keypad for keypress
def scan_keypad():
    key = None
    for i in range(len(keypad_cols)):
        # Activate the column
        keypad_cols[i].low()
        for j in range(len(keypad_rows)):
            if not keypad_rows[j].value():
                key = keypad_layout[j][i]
        # Deactivate the column
        keypad_cols[i].high()
    return key

while True:
    key_pressed = scan_keypad()
    if key_pressed:
        print("Key Pressed:", key_pressed)
    time.sleep(0.2)