User Manual

28 Command Summary

Font File Creation

Matrix Orbital graphic displays are capable of displaying text in a wide variety of styles customizable to

suit any project design. Front files alter the style of text and appearance of the display.

By default, a Matrix Orbital graphic display is loaded with a small filled font in slot one and a future bk bt

16 style in slot two. Both are available at www.matrixorbital.ca/software/graphic_fonts.

The easiest way to create, add, or modify the fonts of any graphic display is through the MOGD# tool.

This provides a simple graphic interface that hides the more complex intricacies of the font file.

Table 22: Example Font File Header

Maximum Width

Character Height

ASCII Start Value

ASCII End Value

104

106

The font file header contains four bytes: First, the number of columns in the widest character; usually

‘w’, second, the pixel height of each character, and finally, the start and end values of the character

range. The range represents the values that must be sent to the display to trigger the characters to

appear on the screen. In the example, the decimal values corresponding to the lowercase letters ‘h’

through ‘j’ will be used resulting in the range shown.

Table 23: Example Character Table

MSB

LSB

Width

The character table contains information that allows the display to locate each individual character in a

mass of character data. Each character has three bytes; two indicating it’s offset in the character data

and one indicating its width. The offset takes into account the header and table bytes to point to the

first byte of the character data it references. The first byte of the file, maximum width, has an offset of

zero. The width byte of each character can be identical as in a fixed width font, or in our case, variable.

The character table will become clearer after analyzing the final part of the font file, character data.

Table 24: Character ‘h’

Bitmap

Table 25: Character ‘h’ Data

132

152

198