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Matrix Orbital GLK24064-25 Legacy User Manual

Page 32

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Figure 20: Bitmaps for h, i, and j

Now the bitmaps have to be converted to bytes. If the font is 8 bits high, it becomes a fairly simple job

because each vertical column is simply one byte (lsb at the top). In this case, however, the font is only 7 bits

high so the bytes ’wrap around’.

Figure 21: Bytes for a 7 Bit High Font

We’ve marked in the bits that are set for the letter "h". Remember that the bytes are ’inverted’, i.e., the

LSB is at the top. Each byte is shown in a different colour in the diagram. When the bytes are straightened

out, it’s simple enough to find their hex values, which are shown in the diagram above each byte. Trailing

zero bytes at the end of narrow characters are not included in the file.

Table 9: Example of a Font File

0xFF

0xFF

0X05

0x07

0x68

0x6A

0x00

0x0F

0x05

0x00

0x14

0x03

0x00

0x17

0x04

0x7F

0x04

0x81

0x80

0x07

0xC4

0x3E

0x10

0x02

0x20

0xB1

0x07

The colours refer to:

Font information header

,

character ’h’

,

character ’i’

,

character ’j’

.

Matrix Orbital

GLK24064-25

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