A system and method are provided for controlling a display unit of a mobile terminal which allows for enhanced display capabilities. A controller of the mobile terminal includes an output buffer region allocated within an external memory of the controller to receive and store screen data, and a display interface to transmit the screen data directly to the display unit. Screen data is stored and transmitted based on a clock cycle associated with an internal bus of the controller, thereby increasing display speed and maximizing the capabilities of a high performance, high speed display unit.