IBM 4400 manual Binary Data Byte, Vertical Data Byte Pattern

Chapter 8 Bit Image Graphics

Bit Image Graphics

Bit Image Graphics mode is selected when the emulation is in Serial Matrix, Proprinter XL, or Epson FX emulation mode. Bit Image Graphics are created by printing a series of vertical bit image data bytes, which represent the binary code bit pattern. Bit Image mode utilizes the 1 or true bits from a binary data byte to print dot patterns. These data bytes are actually the binary equivalent of ASCII character decimal values 0 through 255. Figure 26 shows the binary data byte bit pattern for the ASCII character A (hex 41, decimal 65).

MSB

Figure 26. Binary Data Byte

If this data byte is rotated vertically, the result is a vertical data byte pattern with the most significant bit (MSB) at the top as shown in Figure 27.

MSB

MSB

Figure 27. Vertical Data Byte Pattern

If each 1 or true bit is plotted, the result is a Bit Image plot of the ASCII character A. The relationship of ASCII character, decimal value, and Bit Image plot is shown in Figure 28.

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