Programming 73
Font Loading
Character Bitmap DataA character is made up of a bitmap the size of which is:
Char. width (X) * Char. Height (Y) bytes.
COLUMN
0 1 2
0
4
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| MSB | LSB |
| MSB |
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Row 1 |
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| =03H |
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| =FFH |
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| =80H |
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The bitmap data consists of bitmap patterns for each character in a character set for which the parameter Char_width in the Char_matrix table is set to a value between 1 and 24. A character that has its Char_width set to zero, is not included in the bitmap data.
The bitmap for one character is then defined according to the following table:
Example • In this example, each row consists of 3 columns equal to 3 bytes.
(COL 0, ROW Ystart) , (COL 1, ROW Ystart) , (COL 2, ROW Ystart)
(COL 0, ROW Ystart+1) , (COL 1, ROW Ystart+1) , (COL 2, Ystart+1)
COL 0, ROW Ystart+Yheight), (COL 1, ROW Ystart+Yheight ), (COL 2, ROW
Ystart+Yheight)
In order to minimize the required storage space, only rows between Ystart and Ystart+Yheight are included in the character bitmap.
09/14/2009 | TTP 2000 Technical Manual |