Dot Patterns And Densities
Graphics
The ANSI emulation graphics mode provides both horizontal and vertical dot placement plotting methods. These methods enable the printing of ASCII characters in their binary code form. Since each character has a unique pattern of 1’s and 0’s (dots and voids) that make up its binary code, the correct placement of these binary forms enables you to form larger images.
For clarity in the text, a binary 1 (a printed dot) will be shown as an X and a binary 0 (empty dot position) will be shown as a 0.
In the graphics mode, only the low order six bits of a
(?)is represented by the binary number 0111111 (bit 7 - bit 1). Since only the first 6 bits are used, a “?” would print six dots on the paper. A lowercase “j” is represented by 101010 which would print the following:
Horizontal Graphics / Vertical Graphics
0X0X0X0 LSB LSB MSBX
0 X 0
X MSB
NOTE: When plotting data, the Least Significant Bit (LSB), Bit 1, is printed first (left or top bit position) and the Most Significant Bit (MSB), Bit 6, is printed last (right or bottom bit position).
Notice that in the horizontal graphics mode, the characters are printed on a single horizontal dot row. In vertical graphics mode, the characters are printed six dots high, a character per dot column.
Using a series of question mark (that prints all dots) characters in a horizontal graphic produces a one dot high solid line across the paper. The same character in vertical graphics mode products a six dot high band across the paper.
Graphs, charts, and pictures can be produced by repeating, omitting, and mixing characters across a page.
Dot Patterns And Densities
Table 10 lists the dot patterns for each of the ASCII characters. Each ASCII character represents six dot positions (or dots) and their spacing is dependent on the density selected. With a density of 60 and 70 DPI, the dots are spaced 1/60 and 1/70 inch apart respectively. At 120 and 140 CPI, each character represents six dots spaced 1/120 and 1/140 inch apart. At 180 and 210 DPI densities, the dots are spaced 1/180 and 1/210 inch apart.
The ASCII characters needed to cover all dot/void combinations are listed in the chart below. Other valid character combinations (although repeat patterns of the characters in the chart) are hex
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