User`s manual

10–3Graphics
Making a Bit Image Pattern
A Bit Image pattern is produced in four steps:
1. On a quadrille pad or graph paper, lay out the graphic pattern you want
to print and divide the pattern into vertical data bytes.
2. Determine the decimal equivalent of each bit image data byte required
to produce your pattern. (See Figure 10–1.)
3. Write a program to generate the complete pattern.
4. Enter and run the program on the host computer.
MSB
MSB
87654321
8
7
6
5
4
3
2
1
MSB : Most Significant Bit
Figure 10–2. Vertical Data Byte Pattern
How to Produce Bit Images
The binary data byte bit pattern for the ASCII character A (hex 41, decimal
65) is pictured in Figure 10–2. If we rotate this data byte clockwise, the result
is a vertical data byte pattern with the most significant bit (MSB) at the top.
If we print each 1 (true) bit as a dot, the result is a bit image of ASCII
character A. The relationship of the ASCII character, its decimal value, and
its bit image plot is shown in Figure 10–3. All 8 bits of a data byte are used
in the Correspondence (NLQ) and Data Processing (DP) print modes. The
High Speed (HS) print mode uses only the six most significant bits of the
data byte. Data bytes are identified by either their binary, octal, hexadecimal,
or decimal equivalents. These numeric equivalents are combined to form a
graphic pattern, such as that illustrated in Figure 10–1.
Bit Image plotting is not limited to printable ASCII characters. You can print
bit Image patterns for any 8–bit data byte with decimal values ranging from 0
to 255. (The U.S. ASCII character set is in Appendix C.)