Microcom 324M, Operator'S Manual

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Downloadable Fonts Chapter 7
7-6 324M/424M Operator’s Manual - 880026-0144
(Word is a 16-bit value, Byte is an 8-bit value, and Label is a location within the file)
Label start:
the beginning of the file
Word, Word, lookup_table_offset
distance in bytes from start to beginning of
lookup_table (4 bytes)
Word tallest_char
height of graphic image in dots
Word widest_char Width of graphic image in dots
Byte default_spacing
Default spacing, usually 0
Byte byte_width
Width of graphic image in bytes
Byte first_char
20 HEX
Byte last_char
20 HEX
Byte default_char 20 HEX
Label lookup_table
beginning of lookup table
Word char_offset [last_char-first_char]
an array of offsets, one for each character in
font. Each offset is the distance, in bytes,
from the start to the beginning of the
corresponding character’s data structure.
The first word in this array is the offset to the
first character’s data; the last word is the
offset to the last character’s data.
Label first_char_data
the beginning of the graphic image data
Word char_height
height of this character’s bitmap in dots
Word char_width
width of the graphic image in dots
Byte bitmap_data[char_height][byte_width]
bitmap of character, 2d array. The most
significant bit of the first byte in each row,
prints as the right most dot of the character,
and the first row is the bottom row when
printed.
7.6 Downloadable Font Command Summary
The following commands refer to the use of downloadable fonts and graphics:
^A ^D COMMAND
100 Clear User RAM:
This command clears all downloadable fonts, graphics, and stored label
formats.