HPRT PPTII-A, Руководство по программированию

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PPTII-A Programming Manual
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B.1 General Description
The printer operates in two print modes: standard mode and page mode. In standard mode, the printer
prints and feeds paper each time it receives print data or paper feed commands. In page mode, all the
received print data and paper feed commands are proce ssed in the specified memory, and the printer
executes no operation. All the data in the memory is then printed when an ESC FF or FF command is
received.
For example, when the printer receives the data "ABCDEF" <LF> in standard mode, it prints "ABCDEF"
and feeds the paper by one line. In page mode, "ABCDEF" is written to the specified printing area in
memory, and the position in memory for the next print data is shifted by one line.
The ESC L command puts the printer into page mode, and all commands received thereafter are
processed in page mode. Executing an ESC FF command prints the received data collectively, and
executing an FF command restores the printer to standard mode after the received data is printed
collectively. Executing an ESC S command restores the printer to standard mode without printing the
received data in page mode; the received data is cleared from memory instead.
B.2 Setting Values in Standard and Page Modes
1) The available commands and parameters are t he same for both standard and page modes. However,
these values can be set indepe ndently in each mode for the ESC SP , ESC 2 , ESC 3 , and FS S
commands. For these commands, different settings can be stored for each mode.
B.3 Formatting of Print Data in the Printable Area
1) The printable area is set by ESC W. If all printing and feeding operations are complete before the
printer receives the ESC W command, the left side (as you face the printer) is taken as the origin (x0,
y0) of the printable area. The printable rectangular area is defined by the length (dx dots) extending
from and including the origin (x0, y0) in the x di rection (perpendicular to the paper feed direction), and
by the length (dy dots) in the y direction (paper feed direction). (If the ESC W command is not used, the
printable area remains the default value.)
2) When the printer receives print data after ESC W sets the printable area and ESC T sets the printing
direction, the print data is formatt ed within the printable area so that point A in Figure B.2 is at the
beginning of the printable area as a default value. (When a character is pr inted, point A is the baseline.)
Print data containing downloaded bit images or bar codes is formatted so that the bottom point of the
left side of the image data (point B in Figur e B.3) is aligned with the baseline.
3) If the print data (including charac ter spacing) exceeds t he printable area before the printer receives a
command (e.g., LF or ESC J ) that includes line feeding, a line feed is executed aut omatically within the
printable area. The print position, therefore, moves to the beginning of the next line. The line feed
amount depends on the values set by commands (such as ESC 2 and ESC 3 ).
4) The default value of the line spacing is set to 1/6 inch and corresponds to 31 dots in the vertical
direction. If print data for the next line contains extended characters that are higher than double-height
characters, bit images taking up two or more lines, or bar codes higher than normal characters, the
amount of line feeding may be insufficient, resulting in overlapping of the characters' higher-order dots
with the previous line. To avoid this, increase the amount of line spacing.
Example