- Introduction - This is the source code for the PTP daemon (PTPd) implementing the Precision Time Protocol (PTP) version 2 as defined by 'IEEE Std 1588-2008'. PTP provides precise time coordination of Ethernet LAN connected computers. It was designed primarily for instrumentation and control systems. - Use - PTPd can coordinate the clocks of a group of LAN connected computers with each other. It has been shown to achieve microsecond level coordination, even on limited platforms. The 'ptpd' program can be built from the included source code; see the release notes about platform compatibility. To use the program, run 'ptpd' on a group of LAN connected computers. Compile with 'PTPD_DBG' defined and run with the '-c' argument to watch what's going on. If you are just looking for software to update the time on your desktop, you probably want something that implements the Network Time Protocol. It can coordinate computer clocks with an absolute time reference such as UTC. - Legal notice - PTPd was written by using only information contained within 'IEEE Std 1588-2008'. IEEE 1588 may contain patented technology, the use of which is not under the control of the authors of PTPd. Users of IEEE 1588 may need to obtain a license for the patented technology in the protocol. Contact the IEEE for licensing information. PTPd comes with absolutely no warranty.

588分为1588v1和1588v2两个版本，1588v1只能达到亚毫秒级的时间同步精度，而1588v2可以达到亚微秒级同步精度。1588v2被定义为时间同步的协议，本来只是用于设备之间的高精度时间同步，随着技术的发展，1588v2也具备频率同步的功能。现在1588v1基本已被1588v2取代，以下非特殊说明，PTP即表示1588v2

IEEE1888-2008 PTPV2 源码，与IEEE1888-2002PTPV1源码性能有较大不同与提高

IEEE 1588（PTPv2）精确时钟同步协议，主从时钟同步报文抓包文件。

stm32f107在rt-thread上实现1588协议 ptpv2，目前不稳定。