| 摘要 |
PURPOSE:To reduce the burden of a software by constituting the title controller so that a reference access cycle for referring to pattern data which has been placed on a frame buffer space, as pattern data for picture drawing can be executed. CONSTITUTION:A graphic display controller 1 supports a picture drawing control function for interpreting a command transferred from a CPU 3 and generating a desired graphic on a frame buffer 2, and a display control function for displaying the data of the frame buffer 2 on a CRT display device. The execution of a reference access cycle for referring to pattern data which has been placed on the frame buffer 2 space, as pattern data for picture drawing works so that the frame buffer 2 space, and also, the data which has been held in this space can be utilized for picture drawing as the pattern data being in place of a pattern RAM. In such a way, a problem point generated from a physical constraint which a conventional pattern RAM has is solved, a picture drawing function is allowed to have flexibility, and also, the burden of the CPU 3 is reduced, and moreover, high speed picture drawing is attained. |
