Dynapro Technologies Dynapro ET TCS, Application Developer'S Manual

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To down-line load a custom character font, do the following:
1. Design the characters in a matrix 8 dots wide by 10 dots high.
2. Divide the characters into 2 sets of 8 sixels each sixes having 6-bit positions. The upper set is
complete (6-bit sixels) and the lower one is made up of 4-bit sixels. The unused bits in each
of the 4-bit sixels should be zero in the conversions that follow.
3. Convert each sixes to a code representing an ASCII character in the range ? through
~
(63
through 126 decimal) by adding an offset of binary 11111 (decimal 63).
4. Use the resulting codes as the sixel bit patterns in the Down-Line Load Character Font
command. Sixteen such sixel bit patterns are sent for each character thus encoded.
Several shortcuts are possible. Graph paper ruled into rectangles having 80 squares can greatly
simplify designing the custom characters particularly if they are custom borders or other
characters that extend to the edges of the character cell.