  Planar Josephson junctions (JJs), based on common superconductors and III-V
semiconductors, are sought for Majorana states and fault-tolerant quantum
computing. However, with gate-tunable spin-orbit coupling (SOC), we show that
the range of potential applications of such JJs becomes much broader. The
time-dependent SOC offers unexplored mechanisms for switching JJs, accompanied
by the $2\pi$-phase jumps and the voltage pulses corresponding to the
single-flux-quantum transitions, key to high-speed and low-power
superconducting electronics. In a constant applied magnetic field, with Rashba
and Dresselhaus SOC, anharmonic current-phase relations, calculated
microscopically in these JJs, yield a nonreciprocal transport and
superconducting diode effect. Together with the time-dependent SOC, this allows
us to identify a switching mechanism at no applied current bias which supports
fractional-flux-quantum superconducting circuits and neuromorphic computing.
