Matrox RGB-GRAPH
Color Graphics Controller

General Description
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Electronic Diagrams
Summary

General description

The RGB-Graph is a Multibus compatible color graphics video controller board for use with RGB monitors. It is available in several models with maximum resolutions ranging from 256 pixels by 256 pixels by one bit plane to 512 pixels by 512 pixels by four bit planes. The 4 bit plane models can merge bit planes to double the horizontal resolution. The display format is set by the user during the programmed I/O initialization of the board.

The RGB-Graph’s display memory is normally accessed by programmed I/O: Display Memory locations corresponding to pixels are pointed to by the X and Y registers, and are accessed through the Data Register. The X and Y Registers, which contain the pixel’s
horizontal and vertical coordinates respectively, can be accessed by direct I/O or their contents can be modified via the Vector Register. Depending on the command loaded into it, the Vector Register increments or decrements, independently, the X and Y registers, and it can be commanded to automatically write the contents of the Data Register into the Display Memory. The Vector Register is used to rapidly draw horizontal, vertical or angular lines.

The Display Memory can also be accessed by an external DMA controller. When the RGB-Graph is used in DMA mode, it occupies 1K of system address space, that is positioned via straps. The DMA controller does each block transfer into this same 1K address block which is mapped into different areas of the Display Memory by the X and Y Registers. As the transfer proceeds, the X and Y Regi&ters are automatically incremented.

The RGB-Graph also has a fast preset function which uses one command to fill the entire Display Memory with the data contained in the Data Register. Similarily, provision has been made for the Display Memory to be loaded from an external frame grabbing A to D converter. Both operations are completed in one frame period.

When the RGB-Graph is not in DMA Mode, the X and Y Registers are clipped so that any data written to pixels outside the display format will not wrap around on the Display. This provides a total working area, displayed and non-displayed, of 4096 pixels by 4096 pixels for all formats.

The following list briefly describes some of the major features of the Matrox RGB-GRAPH controller:

  • 512 x 512 x 4 or 1024 x 512 x 2 SOFTWARE SELECTABLE RESOLUTION
  • MULT1BUS PLUG-IN
  • 4 BIT PLANES
  • PAN and SCROLL
  • VECTOR PLOT
  • EXPANDABLE
  • SCREEN PRESET
  • BIT PLANE WRITE ENABLE
  • INDEPENDENT X and Y ZOOM
  • DMA TRANSFERS
  • HARDWARE CLLPPING
  • VIDEO BUS
  • LIGHT PEN INTERFACE
  • VIDEO OUTPUT ENABLE
  • PROGRAMMABLE DISPLAY FORMAT

Electronics diagrams

RESOLUTION

  • RGB-Graph/16-1. 256 pixels x 256 pixels x 1 bit
  • RGB-Graph/16-4. 256 pixels x 256 pixels x 4 bits
  • RGB-Graph/32-1. 512 pixels x 256 pixels x 1 bit
  • RGB-Graph/32-4. 512 pixels·x 256 pixels x 4 bits
  • RGB-Graph/64-1. 512 pixels x 512 pixels x 1 bit
  • RGB-Graph/64-4. 512 pixels x 512 pixels x 4 bits
  • The horizontal resolution of the -4 models can be doubled by
    sacrificing two bit planes.

SPECIAL FUNCTIONS

– Independent X and Y Zoom:

  • X-Zoom by 1,2,3,4,5,6,7, or 8
  • Y-Zoan by 1,2, or 4

– Scroll and Pan:

  • horizontal pan with single pixel precision
  • vertical scroll with 8 pixel precision

– Fast preset of display to value in data port

    – DMA access to the Display Memory

      – Light Pen Register

        – Vector Plot

          – Access to each bit plane can be ,independently software disabled