The serial port can be used to control the master arduino component, and get data from it. The master can relay messages between its serial port and slave components.
####Available serial commands
RAS - Read all sensors
LAS - List all sensors
SAS <board number> <value> - Send a value to a board
RAS command:
<sensor name> <value>
<sensor name> <value>
...
LAS command:
Register <board name> <board number> <sensor name> <sensor number>
Register <board name> <board number> <sensor name> <sensor number>
...