TallyGenicom Matrix Printer Programmer's Manual page 172

Definition of the Character Grid
NLQ characters consist of
18 vertical dots and 12 hori-
zontal dots.
Within this grid every num-
bered line or gap can be oc-
cupied, including the lowest
and the furthest right line.
You should, however, leave
one or two columns empty,
so that neighboring charac-
ters do not touch.
For each column of the NLQ
character it is necessary to de-
fine 3 Bytes. Each bit of the
data bytes corresponds to a
certain value. The example on
the right shows the as-
signment of print dots to data
bytes and the calculation of
the values.
In order to determine the nu-
meric value of a column, it is
necessary to first of all add the
values of the 3 bytes separa-
tely. A byte with no print dot
receives the numeric value 9.
128
64
32
16
8
4
2
1
128
64
32
16
8
4
2
1
128
64
1 2 3 4 5 6 7 8 9 10 11 12
128
64
32
First
16
Data Byte
8
4
2
1
128
64
32
Second
16
Data Byte
8
4
2
1
Third
128
Data Byte
64
Download Character Generator
128
64
= 229
4
1
16
8
= 28
4
64 = 64
89