We study the ring resonator under a dynamic modulation. Each ring resonator supports a set of resonant modes with an equal spacing. We find that the system exhibits a spectral Bloch oscillation along the frequency axis when we introduce a frequency detuning in the modulation frequency. A periodic switching of the detuning brings out a unidirectional translation of the frequency of light. Moreover, in an array of rings, each of which is dynamically modulated with a different phase, we see topologically-protected edge states. Our work points to a new capability for the control of light in the frequency space.