  We describe an approach to the integrated control and measurement of a
large-scale superconducting multiqubit circuit using a proximal coprocessor
based on the Single Flux Quantum (SFQ) digital logic family. Coherent control
is realized by irradiating the qubits directly with classical bitstreams
derived from optimal control theory. Qubit measurement is performed by a
Josephson photon counter, which provides access to the classical result of
projective quantum measurement at the millikelvin stage. We analyze the power
budget and physical footprint of the SFQ coprocessor and discuss challenges and
opportunities associated with this approach.
