Blackboard

Interface

Constructor

Blackboard(addr=MCAST_GRP, port=MCAST_PORT, read_size=READ_SIZE, TTL=MULTICAST_TTL)

• addr: This is the network address to connect to. It must be an unreserved, available network block that supports the Multicasting protocol. It will default to 244.1.1.1.
• port: This is the port on the network address the Blackboard will connect to. It will default to 5007.
• read_size: This will specify the standard read size when getting data from the network address. It will default to 256 bytes.
• TTL: This is the number of times the signal will propagate through the network before being cut off. It will default to 32.

Methods

• write_json(channel, data): This will write the specified data to the specified channel. The channel can be any arbitrary string.
• get(channel): This will return the most recent piece of data received on a specified channel.
• register_callback(channel, f): This will add a callback function that will be called when a specific channel gets data. The callback must be a function that gets a single argument of the data from the channel.
• is_open(): This function will return True if the Blackboard is connected to the network, and False otherwise.