  A honeycomb Floquet lattice with helically rotating waveguides and an
interface separating two counter-propagating subdomains is analyzed. Two
topologically protected localized waves propagate unidirectionally along the
interface. Switching can occur when these interface modes reach the edge of the
lattice and the light splits into waves traveling in two opposite directions.
The incoming mode, traveling along the interface, can be routed entirely or
partially along either lattice edge with the switching direction based on a
suitable mixing of the interface modes.
