text: from PikaObj import *
  import PikaStdLib
  import PikaPiZero
  import STM32G0
  
  lcd = PikaPiZero.LCD()
  lcd.init()
  lcd.clear('white')
  mem = PikaStdLib.MemChecker()
  key = PikaPiZero.KEY()
  key.init()
  time = STM32G0.Time()
  h = 10
  w = 10
  x = 10
  y = 10
  x_last = x
  y_last = y
  is_update = 0
  print('mem used max:')
  mem.max()
  lcd.fill(x, y, w, h, 'blue')
  while True:
      key_val = key.get()
      if key_val != -1:
          x_last = x
          y_last = y
          is_update = 1
      if key_val == 0:
          x = x + 5
      if key_val == 1:
          y = y - 5
      if key_val == 2:
          y = y + 5
      if key_val == 3:
          x = x - 5
      if is_update:
          is_update = 0
          lcd.fill(x_last, y_last, w, h, 'white')
          lcd.fill(x, y, w, h, 'blue')
  