SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
The MAC module supports the IEEE 1588-2002 Timestamp Precision Time Protocol (PTP) and the IEEE 1588-2008 Advanced Timestamp features. PTP enables precise synchronization of clocks in measurement and control systems implemented with technologies such as network communication, local computing, and distributed objects. The PTP applies to systems communicating by a local area network supporting multicast messaging. This protocol enables heterogeneous systems that include clocks of varying inherent precision, resolution, and stability to synchronize. The protocol supports system-wide synchronization accuracy in the sub-microsecond range with minimal network and local clock computing resources.
The PTP is transported over UDP/IP. The system or network is classified into master and slave nodes for distributing the timing and clock information. Figure 15-10 shows the process that PTP uses for synchronizing a slave node to a master node by exchanging PTP messages.
As shown in Figure 15-10, the PTP uses the following process:
Most of the PTP implementation is done in the software above the UDP layer. However, the hardware support is required to capture the exact time when specific PTP packets enter or leave the Ethernet MAC. This timing information is captured and returned to the software for the proper implementation of PTP with high accuracy.