1  import time
 2  import board
 3  import busio
 4  import digitalio
 5  import adafruit_74hc595
 6  
 7  spi = busio.SPI(board.SCK, MOSI=board.MOSI)
 8  
 9  latch_pin = digitalio.DigitalInOut(board.D5)
10  sr = adafruit_74hc595.ShiftRegister74HC595(spi, latch_pin)
11  
12  pin1 = sr.get_pin(1)
13  
14  while True:
15      pin1.value = True
16      time.sleep(1)
17      pin1.value = False
18      time.sleep(1)