| 摘要 |
A microprocessor based data processing system including a microprocessor (40), a memory unit (42), and a display unit (22) is provided with a programmable graphics generator (44) that transfers graphics information from the memory unit (42) to the display unit (22) in response to and under the control of a set of display instructions also stored in the memory unit (42). The graphics generator (44) includes a first addressing unit (82) for sequentially accessing the display instructions from the memory unit (42); a control unit (88,90) for receiving, storing and decoding such instruction and for issuing supervisory and control signals in response to the binary state of each instruction; a second addressing unit (84) for accessing graphics information from the memory unit (42) in response to the supervisory signals from the control unit (88,90); and a third addressing unit (86) for accessing movable object graphics stored in the memory unit (42). A movable object generator section (448) of the programmable generator (44) includes circuit elements (140) for determining the horizontal position of the movable object only; the vertical position of the object displayed is modified by rewriting the picture data of the object at a new location within a block (288a to 288e) of graphics information corresponding to each movable object. The entire block of graphics information, including the picture data of the object, is communicated to the display unit (22) and displayed as a vertical column (430 to 440). Also disclosed is a method and apparatus for formating and transferring the graphics information in sequentially ordered bytes so that the binary states of each byte select the color and luminance characteristics used to display each byte of graphics information. Additional features of the invention include a sound generator (46) capable of selectively providing a plurality of audio signals. |
