import time
import RPi.GPIO as GPIO

# Define GPIO pins
SER = 17  # Serial data input
SRCLK = 27  # Shift register clock
RCLK = 22  # Storage register clock

# Segment data for digits 0-9
SEGMENTS = [
    0b00111111,  # 0
    0b00000110,  # 1
    0b01011011,  # 2
    0b01001111,  # 3
    0b01100110,  # 4
    0b01101101,  # 5
    0b01111101,  # 6
    0b00000111,  # 7
    0b01111111,  # 8
    0b01101111,  # 9
]

def shift_out(data):
    for i in range(8):
        GPIO.output(SER, (data >> i) & 1)
        GPIO.output(SRCLK, GPIO.HIGH)
        GPIO.output(SRCLK, GPIO.LOW)

def main():
    GPIO.setmode(GPIO.BCM)
    GPIO.setup(SER, GPIO.OUT)
    GPIO.setup(SRCLK, GPIO.OUT)
    GPIO.setup(RCLK, GPIO.OUT)
    
    try:
        while True:
            # Display numbers from 0 to 9
            for num in range(10):
                shift_out(SEGMENTS[num])
                GPIO.output(RCLK, GPIO.HIGH)
                GPIO.output(RCLK, GPIO.LOW)
                time.sleep(1)  # Wait for 1 second
            
            # Display numbers from 9 to 0
            for num in range(9, -1, -1):
                shift_out(SEGMENTS[num])
                GPIO.output(RCLK, GPIO.HIGH)
                GPIO.output(RCLK, GPIO.LOW)
                time.sleep(1)  # Wait for 1 second

    finally:
        GPIO.cleanup()

if __name__ == "__main__":
    main()