  The Muon-to-Electron Conversion (Mu2e) Experiment demands a highly precise
magnet and collimator system to achieve a stringent extinction level of
$1\times 10^{-10}$ for out-of-time beam particles. Extinction is ensured by an
AC Dipole system consisting of two magnet components: a 295 kHz system to allow
for the passage of a 590 kHz beam at the nodes, and a 4.42 MHz system to
minimize in-time beam slewing. Both components must be accurately phase-locked
to the Delivery Ring's bunch rate as well as be synchronized with beam
transfers from the Recycler.
  In this paper, we present the design, implementation, and results of a
control system for the Mu2e magnet system based on an Intel Arria 10 FPGA. This
system handles the phase-locking of the magnets to the Delivery Ring, as well
as the phase jumps required for synchronization with transfers from the
Recycler.
