The Inter Integrated Circuit (I2C) module is a serial interface primarily intended for communication with other peripheral or microcontroller devices. Examples of the peripheral devices are: serial EEPROM memories, shift registers, display drivers, serial AD converters, etc. In the dsPIC30F family of devices the I2C module can operate in the following systems:
- the dsPIC30F device is a slave device,
- the dsPIC30F device is a master device in a single-master environment (slave may also be active),
- the dsPIC30F device acts as a master/slave device in a multi-master system (bus collision detection and arbitration available).
The I2C module contains independent I2C master logic and I2C slave logic each generating interrupts based on their events. In multi-master systems, the software is simply partitioned into master controller and slave controller. When the master logic is active, the slave logic remains active also, detecting the state of the bus and potentially receiving messages from itself or from other I2C devices. No messages are lost during multi-master bus arbitration. In a multi-master system, bus collision conflicts with other masters in the system are detected and the module provides a method to terminate and then restart the messages.
The I2C module contains a baud-rate generator. The baud-rate generator does not consume other timer resources in the device. The speed of operation of the module may be standard or fast and it may detect 7-bit and 10-bit addresses.