Printek Emulation
Each graphics sequence contains two bytes (n1 and n2) that specify how many bytes of graphics data follow. N2 can specify values up to 255. If that is sufficient, then n1 is just set to zero. For values greater than 255, n1 comes into play. The n1 byte specifies multiples of 256. For example, to specify 520 bytes of graphics data, use n2 = 8 and n1 = 2. The bytes of graphics data are strung together to create a graphics line that is eight dots high, and (n1 x 256) + n2 dots long. Be sure to provide the amount of graphics data that you specify, because the printer will not leave graphics mode until it has accepted the specified number of data bytes.
If “Data Bits” is set to “7” in the interface setup menu, beware of potential problems in graphics mode. Since the MSB (most significant bit) will always be turned off, it will not be possible to fire the top wire of the print head. Worse yet, the value of n1 or n2 may be changed. For example, if n2 specifies 200 bytes of data, and its MSB is turned off, the printer will only expect 72 bytes of data. It will exit graphics mode, and then try to print the remaining 128 bytes of graphics data as normal text characters. The result will surely not be pretty. To avoid such problems, the use of an
The normal graphics modes allow every dot to be printed. High speed graphics will print twice as fast, but will not allow consecutive dots to be printed.
m DPI Graphics | ESC * m n1 n2 data |
Selects eight wire graphics of density m as listed in the following table for (n1 x 256) + n2 columns of data.
m Density _______
6240 dpi
7240 dpi high speed
8180 dpi
9180 dpi high speed
10144 dpi
11144 dpi high speed
12120 dpi
13120 dpi high speed
14102.86 dpi
15102.86 dpi high speed
1690 dpi
1790 dpi high speed
1880 dpi
1980 dpi high speed
2072 dpi
2172 dpi high speed
2265.45 dpi
2365.45 dpi high speed
2460 dpi
2560 dpi high speed
NOTE: Horizontal movement of the printer's print head is measured in intervals of 1/720 of an inch. Every supported graphics density above is an integral multiple of this resolution. For example, at 60 dpi, dots may be printed every 12/720 of an inch.
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