A system can include a display, a first device, and a second device all operatively connected to a controller. The first and second devices each use or share at least a portion of the display area. The controller is adapted to transmit during a pixel refresh time period of the display a first signal that is received by the first device. The first sync signal indicates a first time period in which a first operation can be performed in the first device. The controller is also adapted to transmit a second sync signal that is received by the second device indicating a second time period in which a second operation can be performed in the second device. The second time period can be during the pixel refresh time period or outside of the pixel refresh time period.