from machine import Pin, Timer
import time

# 定義引腳(段腳 + 位選腳)
pins_segment = [None] * 4
for i in range(4):
  pins_segment[i] = Pin(19-i, Pin.OUT) #

while True:
  for code in range(16):  #
    for i in range(4):  #
      pins_segment[i].value((code >> i) & 1)
    time.sleep_ms(500)