Information processing apparatus having two modules that have independent clock supply sources, control method therefor, and storage medium storing control program therefor

An information processing apparatus that is capable of reducing deviation of cycles of modules having independent clock supply sources. A processor controls a first module to operate in synchronization with a first synchronizing signal supplied from a first timing controller, controls a second module to operate in synchronization with a second synchronizing signal supplied from a second timing controller, measures times of supplying the synchronizing signals to the modules, calculates a time difference between the times when the first timing controller is switched to a second mode where the first synchronizing signal is supplied to the first module based on a setting period after synchronizing the synchronizing signals in a first mode where the first synchronizing signal is supplied to the first module in synchronization with the second synchronizing signal, and changes the setting period when the time difference is more than a threshold.