Technical data

Section 7: Downloading Characters and Fonts
116
Part Two: Specifying the Download Data
Each font character is made up of 48 bytes of data. There are 2 bytes of attribute
data and 46 bytes of character data. This field of 48 bytes must be repeated for
each character. The following text describes the specifications of the attribute
bytes and the character data.
Attribute byte 1 specifies the character type.
Bit Bit Values Functions
7
0
if the character is an
ascender.
Ignored if bit 0 or bit 1 is set to 1.
1
if the character is a
descender
(for example, ’g’).
Ignored if bit 0 or bit 1 is set to 1.
6-2 Currently ignored and
should always be zero.
1,0
0,0
no 12-high expansion.
Bit 7 is valid.
0,1
line-drawing character.
Expand the bottom row 15
down to rows 17, 19, 21,
and 23. Expand the bottom
row 16 down to rows 18,
20, 22, and 24. The
ascender/descender bit 7
above is ignored.
This type mode should be used to create
characters similar to resident font
characters 179 to 223.
1,0 shading character.
Expand the top dots in
rows 1, 3, 5, and 7 down to
rows 17, 19, 21, and 23.
Expand the top dots in
rows 2, 4, 6, and 8 down to
rows 18, 20, 22, and 24. The
ascender/descender bit 7
above is ignored.
This type mode should be used to create
characters similar to resident font
characters 176 to 178.