  DUNE will be the world's largest neutrino experiment due to take data in
2025. Here is described the data acquisition (DAQ) system for one of its
prototypes - ProtoDUNE-SP due to take data in Q4 of 2018. ProtoDUNE-SP also
breaks records as the largest beam test experiment yet constructed, and is a
fundamental element of CERN's Neutrino Platform. This renders ProtoDUNE-SP an
experiment in its own right and the design and construction have been chosen to
meet this scale. Due to the aggressive timescale, off-the-shelf electronics
have been chosen to meet the demands of the experiment where possible. The
ProtoDUNE-SP cryostat comprises two primary subdetectors - a single phase
liquid Argon TPC and a companion Photon Detector. The TPC has two candidate
readout solutions under test in ProtoDUNE-SP - RCE (ATCA-based) and FELIX
(PCIe-based). Fermilab's artDAQ is used as the dataflow software for the
experiment. Custom timing and trigger electronics and software are also
described. Compression and triggering will take the ~480 Gb/s of data from the
front-end and reduce it sufficiently to 20 Gb/s bandwidth to permanent data
storage in CERN's EOS infrastructure.
