code: func (a *MAX7219Driver) Start() (err error) {
  	a.pinData.On()
  	a.pinClock.On()
  	a.pinCS.On()
  
  	a.All(MAX7219ScanLimit, 0x07)
  	a.All(MAX7219DecodeMode, 0x00)
  	a.All(MAX7219Shutdown, 0x01)
  	a.All(MAX7219DisplayTest, 0x00)
  	a.ClearAll()
  	a.All(MAX7219Intensity, 0x0f&0x0f)
  
  	return
  }
docs: // Start initializes the max7219, it uses a SPI-like communication protocol