VSV11 Graphic System

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The VSV11 Graphic System was a raster display system, originally from DEC's Computer Special Systems division. The VSV11 used an odd intermediary approach: although the video output signal was produced by scanning a large raster array memory in the VSV11, the image is specified by a display program held in main memory. The VSV11 used DMA to retrieve the display program from the system's main memory, and converted it to a bit-mapped display-type image stored in the VSV11's raster memory, from where it was displayed.

Screen display refresh was not performed by re-reading the display program; rather, it was done by repetitively scanning the raster memory in the VSV11. The VSV11 was capable of displaying text (using subsidiary display programs for each character), vectors (short and long), points (relative and absolute), and bit-maps of varying sizes.

The VSV11 also supported a H3060 joystick for pointing input.

It was a Q18 QBUS device, which consisted of three different quad boards: an M7061 Sync Generator/Cursor Control module; an M7064 Display Processor module; and one or more M7062 Image Memory modules.

They were connected by an over the back flat cable, which carried the inter-board DBUS (Memory Data Bus, covered in Section 4.3.3 of the 'VSV11/VS11 Raster Graphics System Option Description'). They also plugged into a standard Q/CD QBUS backplane, which carried the Video Bus (covered in Section 6.3.9) on the CD interconnect; all the cards therefore had to plug into adjacent slots.

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