Wang 5536 - Page 19

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2.3.1.3 Character Generation (Figure 2-4)
Video dis play logic continuously reads characters from CRT memory. Either
of two character ROMs forms each character. Each ROM converts character
codes into illuminated-dot sequences that form selected charactt:1- shapes on
the display during each scan line. ROM output is serialized and supplied
to the video output circuit. Video display logic also reads a special
control memory that determines the display status of each character
(normal, intensified, underlined, etc.).
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CRT MEMORY
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GENERATION
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ADDRESS BUS-·
DATA BUS
Figure 2-4. Keyboard Interface
2-5
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