A data storage system for an electronic color printer which stores data according to the type of information the data represents. When the data represents area fill and image information, the data is stored in the page buffer according to mode A of the invention wherein a plurality of pixels are all defined to have the same color with varying luminance levels. This color is defined in the memory in a uniform color space format. When the data to be stored is representing text or line graphics information, the data is stored in the page buffer according to mode B of the invention. In mode B, two-bit binary values in the page buffer are assigned to each pixel of a multiple-pixel cell. These two-bit values point to additional bytes in the memory block of the page buffer which in turn point to discrete colors in spectrums of 256 colors. Additional data indicates whether the output device is to reproduce the colors by halftoned or non-halftoned techniques. Thus, each pixel within the pixel cell can be printed in a color selected by the color portion of the page buffer. According to mode C of the invention, three separate color maps are defined in binary form by the bit patterns stored in the page buffer memory. Also in mode C, the method used to produce blacks in the output page is specified. By standardizing on the memory allocated to the page and utilizing this memory in different ways according to the nature of the inputted information, the printed page can be accurately stored with a minimum of memory space and without a reduction in perceived printing quality.

A display control circuit provides the logical determination of display information for each dot point of a color television or other display device used in connection with an electronic game for displaying up to eight "targets", as well as background information, according to a preassigned software defined priority whereby hardware circuitry encodes background-to-target software information and then decodes all game display circuit information to generate a color display code to the color television-type display device, this hardware utilizing a reduced space on a large scale integrated (LSI) circuit.

A microprocessor based data processing system including a microprocessor, a memory unit, and a display unit is provided with a programmable graphics generator that transfers graphics information from the memory unit to the display unit in response to and control of a set of display instructions also stored in the memory unit. The graphics generator includes a first addressing unit for sequentially accessing the display instructions from the memory unit; a control unit 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 for accessing graphics information from the memory unit in response to the supervisory signals from the control unit; and a third addressing unit for accessing movable object graphics stored in the memory unit.

A video display processor (VDP) for use with a central processing unit, a video RAM (VRAM) and a video display unit is capable of writing video image data supplied from an external video device such as a television set into the VRAM. The VDP comprises a first input terminal for receiving the external video image data and a second input terminal for receiving horizontal and vertical synchronization signals from the external video device. The VDP generates address data in accordance with the horizontal and vertical synchronization signals and supplies the address data to the VRAM when processing of the external video image data is designated. The VDP also supplies the received external video image data to the VRAM thereby to write the external video image data into addresses of the VRAM designated by the address data. The external video image data may be either color codes representative of colors of display elements of a video image displayed at the external video device or data representative of amplitude levels of an analog video signal outputted from the external video device.

A monochrome image becomes expanded into a color image for storage in a bit mapped color display memory. The color expand operation substitutes color data of one of two designated colors for the "1" or "0" monochrome data of a stored monochrome image. The first color code is substituted for all pixels of the monochrome image represented by a "1" and the second color code is substituted for all pixels of the monochrome image represented by a "0". This color expanded image is then stored in the color display memory which controls the color picture shown to the user. This technique permits storage of commonly used images such as alphanumeric characters of various fonts or icons in a compressed form with one bit per pixel. These images are formed in color using the color expand operation at the time of drawing into the color display memory. Otherwise these images would need to be stored in multiple bit per pixel color form for all desired colors requiring considerable memory for redundant data. This color expanded image may then be combined with the color image stored in a selected part of the display memory and the combined image stored in that selected part of the display memory. Thus monochrome images may be expanded into color images and then combined with color images already in the display in a single operation.