Tally Genicom T5023+ - Manual (Page 149)

Character set commands Definition of characters
T5023/5023+ - Programming Guide 139
Encryption of the dot pattern into a number sequence
Before being transferred to the printer, the dot pattern of a newly defined char-
acter must be encrypted into a sequence of data bytes, i. e. into numbers be-
tween 0 and 255.
For this, the grid is divided into columns each of eight dot positions lying one be-
neath the other (squares). The encryption of such a dot column takes place ac-
cording to the following system:
Each square of the dot column from the top to the bottom in descending order is
assigned a value of a power of two:
The encryption of the dot column is the total of the powers of two of all squares
which contain a dot, for example:
The total of a column, which contains no dots, is 0; the total of a column, in which
all the dots are set, is 255.