Printronix P6000L, User'S Reference Manual

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4-3 Graphics
Plotting a Bit Image Pattern
A Bit Image pattern can be developed as follows:
1. Layout the graphic to be printed on a quadrille pad or graph paper.
2. Determine the decimal equivalence of each Bit Image data byte required to produce the
pattern.
3. Write a program to generate the complete pattern.
4. Enter and run the program on the host computer.
Figure 4-4 illustrates steps 1 and 2. Eight vertical cells are used to create the Bit Image pattern
corresponding to the eight bits of the vertically rotated data byte. Dots are placed in the cells to
provide a visual representation of the graphic to be printed. Each dot corresponds to a 1" or
true bit in the data byte. In this example, seven Bit Image data bytes are required to create the
dot pattern. These seven data bytes must be specified in the written program (step 3) to generĆ
ate the entire pattern.
73
146
36
255
36
146
73 DECIMAL
VALUES
128
64
32
16
8
4
2
1
DECIMAL
WEIGHTS
7th BIT IMAGE DATA BYTE
2nd BIT IMAGE DATA BYTE
1st BIT IMAGE DATA BYTE
Figure 4-4. Bit Image Pattern Plan
A Bit Image pattern is easily defined by determining the decimal equivalent of the binary data
byte. This decimal value may then be included in a program data statement that generates the
final Bit Image pattern. To determine the decimal value of a data byte, each dot's decimal
weight is added together. For the seven bytes shown in Figure 4-4, the decimal values are comĆ
puted as shown in Table 4-1.