I2C Bus Protocol

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).

DLN-series adapters can operate as master devices (read I2C Master Interface). Some DLN adapters can also operate as slave devices (read I2C Slave Interface).

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.