Connecting multiple M5Stack units

• The grove port (a.k.a. Port A) on the device supports three kind of units; I²2, GPIO and UART, but only one protocol at a time.
• The unit protocols can be distinguished by their corresponding color:
  • Red for I²C (Inter-Integrated Circuit)
  • Black for GPIO (General Purpose Input/Output)
  • Blue for UART (Universal Asynchronous Receiver/Transmitter)
• Although grove Port A can handle all three protocols for one connected unit, it cannot handle multiple protocols on one port at once. To combine multiple units we need to expand Port A.
• To expand the ports of an Atom device we need the Port ABC base.
  It will expand the device with an A (I²C), B (GPIO) and a C (UART) port.

  

Combining I²C units

• Combining I²C units does not require expanding port A.
  Every I²C unit has an unique hardware address which allows the controller to distuingish the data from different units.
  I²C units with different hardware addresses can be daisy-chained with an Hub unit.

  

• The hub unit does not require any additional codeblocks.
• Units with the same hardware address (similar units, e.g. three Ultrasonic units) cannot be daisy chained with a Hub unit. For this purpose we need a so-called I²C multiplexer or PaHub.
  

  

• The PaHub requires additional code and must be added to UIFlow2 blocks as a unit. The units port setting needs to be changed to the PaHub and the corresponding port number on the PaHub.