Chapter 38Inter-Integrated Circuit (I2C)38.1 IntroductionNOTEFor the chip-specific implementation details of this module'sinstances see the chip configuration information.The inter-integrated circuit (I2C, I2C, or IIC) module provides a method ofcommunication between a number of devices. The interface is designed to operate up to100 kbit/s with maximum bus loading and timing. The I2C device is capable of operatingat higher baud rates, up to a maximum of clock/20, with reduced bus loading. Themaximum communication length and the number of devices that can be connected arelimited by a maximum bus capacitance of 400 pF. The I2C module also complies withthe System Management Bus (SMBus) Specification, version 2.38.1.1 FeaturesThe I2C module has the following features:• Compatible with The I2C-Bus Specification• Multimaster operation• Software programmable for one of 64 different serial clock frequencies• Software-selectable acknowledge bit• Interrupt-driven byte-by-byte data transfer• Arbitration-lost interrupt with automatic mode switching from master to slave• Calling address identification interrupt• START and STOP signal generation and detection• Repeated START signal generation and detection• Acknowledge bit generation and detection• Bus busy detection• General call recognitionKL25 Sub-Family Reference Manual, Rev. 3, September 2012Freescale Semiconductor, Inc. 687
