Plotting a Bit Image Pattern
259
Figure 28. Vertical Data Byte Pattern
The byte in the previous example (or any other byte) can be identified by i ts
binary, octal, hexadecimal, or decimal equivalent and subsequently c anb e
used to generate a Bit Image pattern. A table of the standard ASCII character
set and equivalences is included in Appendix A. Use this table to quickly
identify the various equivalences of ASCII characters. Bit Image plotting is not
limited to printable ASCII characters; bit image patterns can be plotted for any
8-bit data byte with decimal values ranging from 0 through 255.
PlottingaBitImagePattern
A Bit Image pattern can be developed as follows:
1. Lay out 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 29 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
graphictobeprinted.Eachdotcorrespondstoa1ortruebitinthedatabyte.
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 generate the entire pattern.
=A65 =
MSB
128
64
32
16
8
4
2
1
=
ASCII
CHARACTER DECIMAL
VALUE
BINARY
CODE
EQUIVALENT TO VERTICALLY
ROTATEDDATA
BYTE
BITIMAGE
PATTERN