TM 5-6675-316-14
(e) The character shapes are formed on the screen by video dot patterns
which make up the character shapes. The video patterns are stored in a ROM accessed
by the character generator logic. Each different pattern is stored in an address
block which is X bits wide, and Y bits high, forming a matrix.
(f) Data bits are stored in the matrix block in locations representing the
physical shapes of the characters or symbols.
(g) When a character key is depressed, a modulating pulse stream is
generated which is fed into the video amp in sequence with the sweep of the horizon-
tal scan line. Each spike on the modulating pulse stream produces a bright spot on
the CRT. As each succeeding line is scanned, the video pulse stream changes,
finally producing the complete character. The sequence takes place over the full
width of the number of characters selected in each line of print, up to the maximum
of 64 characters per line.
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