  In this work, we propose a completely general method to pump the gapped
topological modes of a lattice of optical waveguides by controlling the
propagation constant of an auxiliary waveguide and its coupling to the main
lattice. In this way, we can transform a single-waveguide excitation on the
auxiliary waveguide into a specific mode of the lattice. We also demonstrate
the possibility of transferring supermodes between two waveguide lattices using
the same method. We illustrate the results by pumping and transferring the
topological modes of Su-Schrieffer-Heeger lattices. For both scenarios, we show
that purities above 99\% can be achieved with parameter values within
experimental reach. Additionally, we demonstrate how the technique can be used
to pump the bulk modes of the lattice for low number of waveguides or enable
mode conversion between waveguide lattices.
