I2C bus uses two lines – SDA (Serial Data line) and SCL (Serial Clock line). Every device connected to the I2C bus can operate as either I2C master (generates the clock and initiates communication with slaves) or I2C slave (responds when addressed by the master).
The I2C bus is a bidirectional bus, but this does not mean that the data is transmitted in both directions simultaneously. At every particular moment, either master or slave sends data over the I2C bus. The device that sends data to the bus is called Transmitter. The device that receives data from the bust is called Receiver. Most I2C devices can both transmit and receive data. However, some I2C devices are only able to receive data. DLN adapters are capable of transmitting and receiving data.
The I2C bus is a multi-master bus; that means that any number of master devices can be present. The DLN-series adapters support clock synchronization and arbitration to avoid conflicts with other master devices on the same I2C bus. Read Avoiding Conflicts in a Multi-master I2C Bus for details.
The maximum number of slave devices is limited by the address space. Each slave device has a unique address. The I2C bus can use 7 or 10-bit addressing. The DLN-series adapters use 7-bit addressing.