code: async def pixy_init(self, max_blocks=5, cb=None, cb_type=None):
          
          if cb:
              self.digital_pins[PrivateConstants.PIN_PIXY_MOSI].cb = cb  # Pixy uses SPI.  Pin 11 is MOSI.
          if cb_type:
              self.digital_pins[PrivateConstants.PIN_PIXY_MOSI].cb_type = cb_type
          data = [PrivateConstants.PIXY_INIT, max_blocks & 0x7f]
          await self._send_sysex(PrivateConstants.PIXY_CONFIG, data)
docs: Initialize Pixy and enable Pixy block reporting.
          This is a FirmataPlusRB feature.
  
          :param cb: callback function to report Pixy blocks
  
          :param cb_type: Constants.CB_TYPE_DIRECT = direct call or
                          Constants.CB_TYPE_ASYNCIO = asyncio coroutine
  
          :param max_blocks: Maximum number of Pixy blocks to report when many signatures are found.
  
          :returns: No return value.