The MSP Power Management Bus (PMBus) embedded software library is a free C library for enabling PMBus master implementation on MSP microcontrollers that have eUSCI/USCI serial communication peripherals. In addition, the library supports alert response (for host notification in the presence of fault), control line (for turning the slave device on/off), and Packet Error Checking (PEC).
The PMBus specification is an industry-wide standard that can be viewed as a step toward unifying communication standards for power conversion and digital power-management devices. It was developed by the PMBus Implementers Forum (PMBus-IF). The standard uses the widely accepted Inter-Integrated Circuit (I2C) communication protocol for the hardware interface. A number of additional features serve to enhance the basic I2C communication protocol. The PMBus standard is also considered to be an extension to the System Management Bus (SMBus) protocol that was popularized by the SBS Implementers Forum for battery systems.