Precise time synchronization is essential for many real-time systems, for instance in the field of the Industrial Internet of Things. To this end, the IEEE has defined the Precision Time Protocol (IEEE 1588) to synchronize devices in IEEE 802 networks, including Ethernet and its extensions for real-time communication known by the term Time Sensitive Networking (TSN).

This paper analyzes the feasibility of implementing IEEE 1588 Precision Time Protocol based time synchronization and syntonization, using commodity microcontrollers without hardwarebased assistance for timestamping IEEE 1588 messages. A Device Under Test, built on a LiteX and RISC-V based FPGA and running the Tock embedded OS, is used to implement an IEEE 1588 slave clock. This clock synchronizes to a precise Grandmaster clock. A time-to-digital-converter measures the system's synchronization accuracy while subject to internal and external simulated system conditions. The acquired data is analyzed and used to derive conclusions about the impact of specific system conditions and architectural choices on the achievable synchronization accuracy.